Expand parity harness coverage before behavioral drift lands

The landed mock Anthropic harness now covers multi-tool turns, bash flows,
permission prompt approve/deny paths, and an external plugin tool path.
A machine-readable scenario manifest plus a diff/checklist runner keep the
new scenarios tied back to PARITY.md so future additions stay honest.

Constraint: Must build on the deterministic mock service and clean-environment CLI harness
Rejected: Add an MCP tool scenario now | current MCP tool surface is still stubbed, so plugin coverage is the real executable path
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Keep rust/mock_parity_scenarios.json, mock_parity_harness.rs, and PARITY.md refs in lockstep
Tested: cargo fmt --all
Tested: cargo clippy --workspace --all-targets -- -D warnings
Tested: cargo test --workspace
Tested: python3 rust/scripts/run_mock_parity_diff.py
Not-tested: Real MCP lifecycle handshakes; remote plugin marketplace install flows

PARITY.md

@@ -1,6 +1,6 @@
 # Parity Status — claw-code Rust Port
 
-Last updated: 2026-04-03 (`03bd7f0`)
+Last updated: 2026-04-03
 
 ## Mock parity harness — milestone 1
 
@@ -8,6 +8,24 @@ Last updated: 2026-04-03 (`03bd7f0`)
 - [x] Reproducible clean-environment CLI harness (`rust/crates/rusty-claude-cli/tests/mock_parity_harness.rs`)
 - [x] Scripted scenarios: `streaming_text`, `read_file_roundtrip`, `grep_chunk_assembly`, `write_file_allowed`, `write_file_denied`
 
+## Mock parity harness — milestone 2 (behavioral expansion)
+
+- [x] Scripted multi-tool turn coverage: `multi_tool_turn_roundtrip`
+- [x] Scripted bash coverage: `bash_stdout_roundtrip`
+- [x] Scripted permission prompt coverage: `bash_permission_prompt_approved`, `bash_permission_prompt_denied`
+- [x] Scripted plugin-path coverage: `plugin_tool_roundtrip`
+- [x] Behavioral diff/checklist runner: `rust/scripts/run_mock_parity_diff.py`
+
+## Harness v2 behavioral checklist
+
+Canonical scenario map: `rust/mock_parity_scenarios.json`
+
+- Multi-tool assistant turns
+- Bash flow roundtrips
+- Permission enforcement across tool paths
+- Plugin tool execution path
+- File tools — harness-validated flows
+
 ## Tool Surface: 40/40 (spec parity)
 
 ### Real Implementations (behavioral parity — varying depth)
@@ -79,17 +97,23 @@ Last updated: 2026-04-03 (`03bd7f0`)
 - [ ] `modeValidation` — validate against current permission mode
 - [ ] `shouldUseSandbox` — sandbox decision logic
 
+Harness note: milestone 2 validates bash success plus workspace-write escalation approve/deny flows, but the deeper validation/security submodules above are still open.
+
 **File tools — need verification:**
 - [ ] Path traversal prevention (symlink following, ../ escapes)
 - [ ] Size limits on read/write
 - [ ] Binary file detection
 - [ ] Permission mode enforcement (read-only vs workspace-write)
 
+Harness note: read_file, grep_search, write_file allow/deny, and multi-tool same-turn assembly are now covered by the mock parity harness.
+
 **Config/Plugin/MCP flows:**
 - [ ] Full MCP server lifecycle (connect, list tools, call tool, disconnect)
 - [ ] Plugin install/enable/disable/uninstall full flow
 - [ ] Config merge precedence (user > project > local)
 
+Harness note: external plugin discovery + execution is now covered via `plugin_tool_roundtrip`; full lifecycle and MCP behavior remain open.
+
 ## Runtime Behavioral Gaps
 
 - [ ] Permission enforcement across all tools (read-only, workspace-write, danger-full-access)
@@ -98,6 +122,8 @@ Last updated: 2026-04-03 (`03bd7f0`)
 - [ ] Token counting / cost tracking accuracy
 - [x] Streaming response support validated by the mock parity harness
 
+Harness note: current coverage now includes write-file denial, bash escalation approve/deny, and plugin workspace-write execution paths.
+
 ## Migration Readiness
 
 - [ ] `PARITY.md` maintained and honest

rust/MOCK_PARITY_HARNESS.md

@@ -17,6 +17,11 @@ The harness runs these scripted scenarios against a fresh workspace and isolated
 3. `grep_chunk_assembly`
 4. `write_file_allowed`
 5. `write_file_denied`
+6. `multi_tool_turn_roundtrip`
+7. `bash_stdout_roundtrip`
+8. `bash_permission_prompt_approved`
+9. `bash_permission_prompt_denied`
+10. `plugin_tool_roundtrip`
 
 ## Run
 
@@ -25,6 +30,15 @@ cd rust/
 ./scripts/run_mock_parity_harness.sh
 ```
 
+Behavioral checklist / parity diff:
+
+```bash
+cd rust/
+python3 scripts/run_mock_parity_diff.py
+```
+
+Scenario-to-PARITY mappings live in `mock_parity_scenarios.json`.
+
 ## Manual mock server
 
 ```bash

rust/README.md

@@ -56,12 +56,19 @@ Harness coverage:
 - `grep_chunk_assembly`
 - `write_file_allowed`
 - `write_file_denied`
+- `multi_tool_turn_roundtrip`
+- `bash_stdout_roundtrip`
+- `bash_permission_prompt_approved`
+- `bash_permission_prompt_denied`
+- `plugin_tool_roundtrip`
 
 Primary artifacts:
 
 - `crates/mock-anthropic-service/` — reusable mock Anthropic-compatible service
 - `crates/rusty-claude-cli/tests/mock_parity_harness.rs` — clean-env CLI harness
 - `scripts/run_mock_parity_harness.sh` — reproducible wrapper
+- `scripts/run_mock_parity_diff.py` — scenario checklist + PARITY mapping runner
+- `mock_parity_scenarios.json` — scenario-to-PARITY manifest
 
 ## Features
 

rust/crates/mock-anthropic-service/src/lib.rs

@@ -93,6 +93,11 @@ enum Scenario {
     GrepChunkAssembly,
     WriteFileAllowed,
     WriteFileDenied,
+    MultiToolTurnRoundtrip,
+    BashStdoutRoundtrip,
+    BashPermissionPromptApproved,
+    BashPermissionPromptDenied,
+    PluginToolRoundtrip,
 }
 
 impl Scenario {
@@ -103,6 +108,11 @@ impl Scenario {
             "grep_chunk_assembly" => Some(Self::GrepChunkAssembly),
             "write_file_allowed" => Some(Self::WriteFileAllowed),
             "write_file_denied" => Some(Self::WriteFileDenied),
+            "multi_tool_turn_roundtrip" => Some(Self::MultiToolTurnRoundtrip),
+            "bash_stdout_roundtrip" => Some(Self::BashStdoutRoundtrip),
+            "bash_permission_prompt_approved" => Some(Self::BashPermissionPromptApproved),
+            "bash_permission_prompt_denied" => Some(Self::BashPermissionPromptDenied),
+            "plugin_tool_roundtrip" => Some(Self::PluginToolRoundtrip),
             _ => None,
         }
     }
@@ -114,6 +124,11 @@ impl Scenario {
             Self::GrepChunkAssembly => "grep_chunk_assembly",
             Self::WriteFileAllowed => "write_file_allowed",
             Self::WriteFileDenied => "write_file_denied",
+            Self::MultiToolTurnRoundtrip => "multi_tool_turn_roundtrip",
+            Self::BashStdoutRoundtrip => "bash_stdout_roundtrip",
+            Self::BashPermissionPromptApproved => "bash_permission_prompt_approved",
+            Self::BashPermissionPromptDenied => "bash_permission_prompt_denied",
+            Self::PluginToolRoundtrip => "plugin_tool_roundtrip",
         }
     }
 }
@@ -243,6 +258,38 @@ fn latest_tool_result(request: &MessageRequest) -> Option<(String, bool)> {
     })
 }
 
+fn tool_results_by_name(request: &MessageRequest) -> HashMap<String, (String, bool)> {
+    let mut tool_names_by_id = HashMap::new();
+    for message in &request.messages {
+        for block in &message.content {
+            if let InputContentBlock::ToolUse { id, name, .. } = block {
+                tool_names_by_id.insert(id.clone(), name.clone());
+            }
+        }
+    }
+
+    let mut results = HashMap::new();
+    for message in request.messages.iter().rev() {
+        for block in message.content.iter().rev() {
+            if let InputContentBlock::ToolResult {
+                tool_use_id,
+                content,
+                is_error,
+            } = block
+            {
+                let tool_name = tool_names_by_id
+                    .get(tool_use_id)
+                    .cloned()
+                    .unwrap_or_else(|| tool_use_id.clone());
+                results
+                    .entry(tool_name)
+                    .or_insert_with(|| (flatten_tool_result_content(content), *is_error));
+            }
+        }
+    }
+    results
+}
+
 fn flatten_tool_result_content(content: &[api::ToolResultContentBlock]) -> String {
     content
         .iter()
@@ -276,6 +323,7 @@ fn build_http_response(request: &MessageRequest, scenario: Scenario) -> String {
     )
 }
 
+#[allow(clippy::too_many_lines)]
 fn build_stream_body(request: &MessageRequest, scenario: Scenario) -> String {
     match scenario {
         Scenario::StreamingText => streaming_text_sse(),
@@ -326,9 +374,88 @@ fn build_stream_body(request: &MessageRequest, scenario: Scenario) -> String {
                 &[r#"{"path":"generated/denied.txt","content":"should not exist\n"}"#],
             ),
         },
+        Scenario::MultiToolTurnRoundtrip => {
+            let tool_results = tool_results_by_name(request);
+            match (
+                tool_results.get("read_file"),
+                tool_results.get("grep_search"),
+            ) {
+                (Some((read_output, _)), Some((grep_output, _))) => final_text_sse(&format!(
+                    "multi-tool roundtrip complete: {} / {} occurrences",
+                    extract_read_content(read_output),
+                    extract_num_matches(grep_output)
+                )),
+                _ => tool_uses_sse(&[
+                    ToolUseSse {
+                        tool_id: "toolu_multi_read",
+                        tool_name: "read_file",
+                        partial_json_chunks: &[r#"{"path":"fixture.txt"}"#],
+                    },
+                    ToolUseSse {
+                        tool_id: "toolu_multi_grep",
+                        tool_name: "grep_search",
+                        partial_json_chunks: &[
+                            "{\"pattern\":\"par",
+                            "ity\",\"path\":\"fixture.txt\"",
+                            ",\"output_mode\":\"count\"}",
+                        ],
+                    },
+                ]),
+            }
+        }
+        Scenario::BashStdoutRoundtrip => match latest_tool_result(request) {
+            Some((tool_output, _)) => final_text_sse(&format!(
+                "bash completed: {}",
+                extract_bash_stdout(&tool_output)
+            )),
+            None => tool_use_sse(
+                "toolu_bash_stdout",
+                "bash",
+                &[r#"{"command":"printf 'alpha from bash'","timeout":1000}"#],
+            ),
+        },
+        Scenario::BashPermissionPromptApproved => match latest_tool_result(request) {
+            Some((tool_output, is_error)) => {
+                if is_error {
+                    final_text_sse(&format!("bash approval unexpectedly failed: {tool_output}"))
+                } else {
+                    final_text_sse(&format!(
+                        "bash approved and executed: {}",
+                        extract_bash_stdout(&tool_output)
+                    ))
+                }
+            }
+            None => tool_use_sse(
+                "toolu_bash_prompt_allow",
+                "bash",
+                &[r#"{"command":"printf 'approved via prompt'","timeout":1000}"#],
+            ),
+        },
+        Scenario::BashPermissionPromptDenied => match latest_tool_result(request) {
+            Some((tool_output, _)) => {
+                final_text_sse(&format!("bash denied as expected: {tool_output}"))
+            }
+            None => tool_use_sse(
+                "toolu_bash_prompt_deny",
+                "bash",
+                &[r#"{"command":"printf 'should not run'","timeout":1000}"#],
+            ),
+        },
+        Scenario::PluginToolRoundtrip => match latest_tool_result(request) {
+            Some((tool_output, _)) => final_text_sse(&format!(
+                "plugin tool completed: {}",
+                extract_plugin_message(&tool_output)
+            )),
+            None => tool_use_sse(
+                "toolu_plugin_echo",
+                "plugin_echo",
+                &[r#"{"message":"hello from plugin parity"}"#],
+            ),
+        },
     }
 }
 
+#[allow(clippy::too_many_lines)]
 fn build_message_response(request: &MessageRequest, scenario: Scenario) -> MessageResponse {
     match scenario {
         Scenario::StreamingText => text_message_response(
@@ -389,6 +516,100 @@ fn build_message_response(request: &MessageRequest, scenario: Scenario) -> Messa
                 json!({"path": "generated/denied.txt", "content": "should not exist\n"}),
             ),
         },
+        Scenario::MultiToolTurnRoundtrip => {
+            let tool_results = tool_results_by_name(request);
+            match (
+                tool_results.get("read_file"),
+                tool_results.get("grep_search"),
+            ) {
+                (Some((read_output, _)), Some((grep_output, _))) => text_message_response(
+                    "msg_multi_tool_final",
+                    &format!(
+                        "multi-tool roundtrip complete: {} / {} occurrences",
+                        extract_read_content(read_output),
+                        extract_num_matches(grep_output)
+                    ),
+                ),
+                _ => tool_message_response_many(
+                    "msg_multi_tool_start",
+                    &[
+                        ToolUseMessage {
+                            tool_id: "toolu_multi_read",
+                            tool_name: "read_file",
+                            input: json!({"path": "fixture.txt"}),
+                        },
+                        ToolUseMessage {
+                            tool_id: "toolu_multi_grep",
+                            tool_name: "grep_search",
+                            input: json!({"pattern": "parity", "path": "fixture.txt", "output_mode": "count"}),
+                        },
+                    ],
+                ),
+            }
+        }
+        Scenario::BashStdoutRoundtrip => match latest_tool_result(request) {
+            Some((tool_output, _)) => text_message_response(
+                "msg_bash_stdout_final",
+                &format!("bash completed: {}", extract_bash_stdout(&tool_output)),
+            ),
+            None => tool_message_response(
+                "msg_bash_stdout_tool",
+                "toolu_bash_stdout",
+                "bash",
+                json!({"command": "printf 'alpha from bash'", "timeout": 1000}),
+            ),
+        },
+        Scenario::BashPermissionPromptApproved => match latest_tool_result(request) {
+            Some((tool_output, is_error)) => {
+                if is_error {
+                    text_message_response(
+                        "msg_bash_prompt_allow_error",
+                        &format!("bash approval unexpectedly failed: {tool_output}"),
+                    )
+                } else {
+                    text_message_response(
+                        "msg_bash_prompt_allow_final",
+                        &format!(
+                            "bash approved and executed: {}",
+                            extract_bash_stdout(&tool_output)
+                        ),
+                    )
+                }
+            }
+            None => tool_message_response(
+                "msg_bash_prompt_allow_tool",
+                "toolu_bash_prompt_allow",
+                "bash",
+                json!({"command": "printf 'approved via prompt'", "timeout": 1000}),
+            ),
+        },
+        Scenario::BashPermissionPromptDenied => match latest_tool_result(request) {
+            Some((tool_output, _)) => text_message_response(
+                "msg_bash_prompt_deny_final",
+                &format!("bash denied as expected: {tool_output}"),
+            ),
+            None => tool_message_response(
+                "msg_bash_prompt_deny_tool",
+                "toolu_bash_prompt_deny",
+                "bash",
+                json!({"command": "printf 'should not run'", "timeout": 1000}),
+            ),
+        },
+        Scenario::PluginToolRoundtrip => match latest_tool_result(request) {
+            Some((tool_output, _)) => text_message_response(
+                "msg_plugin_tool_final",
+                &format!(
+                    "plugin tool completed: {}",
+                    extract_plugin_message(&tool_output)
+                ),
+            ),
+            None => tool_message_response(
+                "msg_plugin_tool_start",
+                "toolu_plugin_echo",
+                "plugin_echo",
+                json!({"message": "hello from plugin parity"}),
+            ),
+        },
     }
 }
 
@@ -399,6 +620,11 @@ fn request_id_for(scenario: Scenario) -> &'static str {
         Scenario::GrepChunkAssembly => "req_grep_chunk_assembly",
         Scenario::WriteFileAllowed => "req_write_file_allowed",
         Scenario::WriteFileDenied => "req_write_file_denied",
+        Scenario::MultiToolTurnRoundtrip => "req_multi_tool_turn_roundtrip",
+        Scenario::BashStdoutRoundtrip => "req_bash_stdout_roundtrip",
+        Scenario::BashPermissionPromptApproved => "req_bash_permission_prompt_approved",
+        Scenario::BashPermissionPromptDenied => "req_bash_permission_prompt_denied",
+        Scenario::PluginToolRoundtrip => "req_plugin_tool_roundtrip",
     }
 }
 
@@ -441,15 +667,35 @@ fn tool_message_response(
     tool_name: &str,
     input: Value,
 ) -> MessageResponse {
+    tool_message_response_many(
+        id,
+        &[ToolUseMessage {
+            tool_id,
+            tool_name,
+            input,
+        }],
+    )
+}
+
+struct ToolUseMessage<'a> {
+    tool_id: &'a str,
+    tool_name: &'a str,
+    input: Value,
+}
+
+fn tool_message_response_many(id: &str, tool_uses: &[ToolUseMessage<'_>]) -> MessageResponse {
     MessageResponse {
         id: id.to_string(),
         kind: "message".to_string(),
         role: "assistant".to_string(),
-        content: vec![OutputContentBlock::ToolUse {
+        content: tool_uses
-            id: tool_id.to_string(),
+            .iter()
-            name: tool_name.to_string(),
+            .map(|tool_use| OutputContentBlock::ToolUse {
-            input,
+                id: tool_use.tool_id.to_string(),
-        }],
+                name: tool_use.tool_name.to_string(),
+                input: tool_use.input.clone(),
+            })
+            .collect(),
         model: DEFAULT_MODEL.to_string(),
         stop_reason: Some("tool_use".to_string()),
         stop_sequence: None,
@@ -531,14 +777,32 @@ fn streaming_text_sse() -> String {
 }
 
 fn tool_use_sse(tool_id: &str, tool_name: &str, partial_json_chunks: &[&str]) -> String {
+    tool_uses_sse(&[ToolUseSse {
+        tool_id,
+        tool_name,
+        partial_json_chunks,
+    }])
+}
+
+struct ToolUseSse<'a> {
+    tool_id: &'a str,
+    tool_name: &'a str,
+    partial_json_chunks: &'a [&'a str],
+}
+
+fn tool_uses_sse(tool_uses: &[ToolUseSse<'_>]) -> String {
     let mut body = String::new();
+    let message_id = tool_uses.first().map_or_else(
+        || "msg_tool_use".to_string(),
+        |tool_use| format!("msg_{}", tool_use.tool_id),
+    );
     append_sse(
         &mut body,
         "message_start",
         json!({
             "type": "message_start",
             "message": {
-                "id": format!("msg_{tool_id}"),
+                "id": message_id,
                 "type": "message",
                 "role": "assistant",
                 "content": [],
@@ -549,39 +813,41 @@ fn tool_use_sse(tool_id: &str, tool_name: &str, partial_json_chunks: &[&str]) ->
             }
         }),
     );
-    append_sse(
+    for (index, tool_use) in tool_uses.iter().enumerate() {
-        &mut body,
-        "content_block_start",
-        json!({
-            "type": "content_block_start",
-            "index": 0,
-            "content_block": {
-                "type": "tool_use",
-                "id": tool_id,
-                "name": tool_name,
-                "input": {}
-            }
-        }),
-    );
-    for chunk in partial_json_chunks {
         append_sse(
             &mut body,
-            "content_block_delta",
+            "content_block_start",
             json!({
-                "type": "content_block_delta",
+                "type": "content_block_start",
-                "index": 0,
+                "index": index,
-                "delta": {"type": "input_json_delta", "partial_json": chunk}
+                "content_block": {
+                    "type": "tool_use",
+                    "id": tool_use.tool_id,
+                    "name": tool_use.tool_name,
+                    "input": {}
+                }
+            }),
+        );
+        for chunk in tool_use.partial_json_chunks {
+            append_sse(
+                &mut body,
+                "content_block_delta",
+                json!({
+                    "type": "content_block_delta",
+                    "index": index,
+                    "delta": {"type": "input_json_delta", "partial_json": chunk}
+                }),
+            );
+        }
+        append_sse(
+            &mut body,
+            "content_block_stop",
+            json!({
+                "type": "content_block_stop",
+                "index": index
             }),
         );
     }
-    append_sse(
-        &mut body,
-        "content_block_stop",
-        json!({
-            "type": "content_block_stop",
-            "index": 0
-        }),
-    );
     append_sse(
         &mut body,
         "message_delta",
@@ -710,3 +976,28 @@ fn extract_file_path(tool_output: &str) -> String {
         })
         .unwrap_or_else(|| tool_output.trim().to_string())
 }
+
+fn extract_bash_stdout(tool_output: &str) -> String {
+    serde_json::from_str::<Value>(tool_output)
+        .ok()
+        .and_then(|value| {
+            value
+                .get("stdout")
+                .and_then(Value::as_str)
+                .map(ToOwned::to_owned)
+        })
+        .unwrap_or_else(|| tool_output.trim().to_string())
+}
+
+fn extract_plugin_message(tool_output: &str) -> String {
+    serde_json::from_str::<Value>(tool_output)
+        .ok()
+        .and_then(|value| {
+            value
+                .get("input")
+                .and_then(|input| input.get("message"))
+                .and_then(Value::as_str)
+                .map(ToOwned::to_owned)
+        })
+        .unwrap_or_else(|| tool_output.trim().to_string())
+}

rust/crates/rusty-claude-cli/tests/mock_parity_harness.rs

@@ -1,16 +1,26 @@
+use std::collections::BTreeMap;
 use std::fs;
+use std::io::Write;
+use std::os::unix::fs::PermissionsExt;
 use std::path::{Path, PathBuf};
-use std::process::{Command, Output};
+use std::process::{Command, Output, Stdio};
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::{SystemTime, UNIX_EPOCH};
 
 use mock_anthropic_service::{MockAnthropicService, SCENARIO_PREFIX};
-use serde_json::Value;
+use serde_json::{json, Value};
 
 static TEMP_COUNTER: AtomicU64 = AtomicU64::new(0);
 
 #[test]
+#[allow(clippy::too_many_lines)]
 fn clean_env_cli_reaches_mock_anthropic_service_across_scripted_parity_scenarios() {
+    let manifest_entries = load_scenario_manifest();
+    let manifest = manifest_entries
+        .iter()
+        .cloned()
+        .map(|entry| (entry.name.clone(), entry))
+        .collect::<BTreeMap<_, _>>();
     let runtime = tokio::runtime::Runtime::new().expect("tokio runtime should build");
     let server = runtime
         .block_on(MockAnthropicService::spawn())
@@ -22,53 +32,121 @@ fn clean_env_cli_reaches_mock_anthropic_service_across_scripted_parity_scenarios
             name: "streaming_text",
             permission_mode: "read-only",
             allowed_tools: None,
-            seed: seed_noop,
+            stdin: None,
+            prepare: prepare_noop,
             assert: assert_streaming_text,
         },
         ScenarioCase {
             name: "read_file_roundtrip",
             permission_mode: "read-only",
             allowed_tools: Some("read_file"),
-            seed: seed_read_fixture,
+            stdin: None,
+            prepare: prepare_read_fixture,
             assert: assert_read_file_roundtrip,
         },
         ScenarioCase {
             name: "grep_chunk_assembly",
             permission_mode: "read-only",
             allowed_tools: Some("grep_search"),
-            seed: seed_grep_fixture,
+            stdin: None,
+            prepare: prepare_grep_fixture,
             assert: assert_grep_chunk_assembly,
         },
         ScenarioCase {
             name: "write_file_allowed",
             permission_mode: "workspace-write",
             allowed_tools: Some("write_file"),
-            seed: seed_noop,
+            stdin: None,
+            prepare: prepare_noop,
             assert: assert_write_file_allowed,
         },
         ScenarioCase {
             name: "write_file_denied",
             permission_mode: "read-only",
             allowed_tools: Some("write_file"),
-            seed: seed_noop,
+            stdin: None,
+            prepare: prepare_noop,
             assert: assert_write_file_denied,
         },
+        ScenarioCase {
+            name: "multi_tool_turn_roundtrip",
+            permission_mode: "read-only",
+            allowed_tools: Some("read_file,grep_search"),
+            stdin: None,
+            prepare: prepare_multi_tool_fixture,
+            assert: assert_multi_tool_turn_roundtrip,
+        },
+        ScenarioCase {
+            name: "bash_stdout_roundtrip",
+            permission_mode: "danger-full-access",
+            allowed_tools: Some("bash"),
+            stdin: None,
+            prepare: prepare_noop,
+            assert: assert_bash_stdout_roundtrip,
+        },
+        ScenarioCase {
+            name: "bash_permission_prompt_approved",
+            permission_mode: "workspace-write",
+            allowed_tools: Some("bash"),
+            stdin: Some("y\n"),
+            prepare: prepare_noop,
+            assert: assert_bash_permission_prompt_approved,
+        },
+        ScenarioCase {
+            name: "bash_permission_prompt_denied",
+            permission_mode: "workspace-write",
+            allowed_tools: Some("bash"),
+            stdin: Some("n\n"),
+            prepare: prepare_noop,
+            assert: assert_bash_permission_prompt_denied,
+        },
+        ScenarioCase {
+            name: "plugin_tool_roundtrip",
+            permission_mode: "workspace-write",
+            allowed_tools: None,
+            stdin: None,
+            prepare: prepare_plugin_fixture,
+            assert: assert_plugin_tool_roundtrip,
+        },
     ];
 
+    let case_names = cases.iter().map(|case| case.name).collect::<Vec<_>>();
+    let manifest_names = manifest_entries
+        .iter()
+        .map(|entry| entry.name.as_str())
+        .collect::<Vec<_>>();
+    assert_eq!(
+        case_names, manifest_names,
+        "manifest and harness cases must stay aligned"
+    );
+
+    let mut scenario_reports = Vec::new();
+
     for case in cases {
-        let workspace = unique_temp_dir(case.name);
+        let workspace = HarnessWorkspace::new(unique_temp_dir(case.name));
-        fs::create_dir_all(&workspace).expect("workspace should exist");
+        workspace.create().expect("workspace should exist");
-        (case.seed)(&workspace);
+        (case.prepare)(&workspace);
-        let response = run_case(case, &workspace, &base_url);
+
-        (case.assert)(&workspace, &response);
+        let run = run_case(case, &workspace, &base_url);
-        fs::remove_dir_all(&workspace).expect("workspace cleanup should succeed");
+        (case.assert)(&workspace, &run);
+
+        let manifest_entry = manifest
+            .get(case.name)
+            .unwrap_or_else(|| panic!("missing manifest entry for {}", case.name));
+        scenario_reports.push(build_scenario_report(
+            case.name,
+            manifest_entry,
+            &run.response,
+        ));
+
+        fs::remove_dir_all(&workspace.root).expect("workspace cleanup should succeed");
     }
 
     let captured = runtime.block_on(server.captured_requests());
     assert_eq!(
         captured.len(),
-        9,
+        19,
-        "five scenarios should produce nine requests"
+        "ten scenarios should produce nineteen requests"
     );
     assert!(captured
         .iter()
@@ -91,8 +169,32 @@ fn clean_env_cli_reaches_mock_anthropic_service_across_scripted_parity_scenarios
             "write_file_allowed",
             "write_file_denied",
             "write_file_denied",
+            "multi_tool_turn_roundtrip",
+            "multi_tool_turn_roundtrip",
+            "bash_stdout_roundtrip",
+            "bash_stdout_roundtrip",
+            "bash_permission_prompt_approved",
+            "bash_permission_prompt_approved",
+            "bash_permission_prompt_denied",
+            "bash_permission_prompt_denied",
+            "plugin_tool_roundtrip",
+            "plugin_tool_roundtrip",
         ]
     );
+
+    let mut request_counts = BTreeMap::new();
+    for request in &captured {
+        *request_counts
+            .entry(request.scenario.as_str())
+            .or_insert(0_usize) += 1;
+    }
+    for report in &mut scenario_reports {
+        report.request_count = *request_counts
+            .get(report.name.as_str())
+            .unwrap_or_else(|| panic!("missing request count for {}", report.name));
+    }
+
+    maybe_write_report(&scenario_reports);
 }
 
 #[derive(Clone, Copy)]
@@ -100,25 +202,71 @@ struct ScenarioCase {
     name: &'static str,
     permission_mode: &'static str,
     allowed_tools: Option<&'static str>,
-    seed: fn(&Path),
+    stdin: Option<&'static str>,
-    assert: fn(&Path, &Value),
+    prepare: fn(&HarnessWorkspace),
+    assert: fn(&HarnessWorkspace, &ScenarioRun),
 }
 
-fn run_case(case: ScenarioCase, workspace: &Path, base_url: &str) -> Value {
+struct HarnessWorkspace {
-    let config_home = workspace.join("config-home");
+    root: PathBuf,
-    let home = workspace.join("home");
+    config_home: PathBuf,
-    fs::create_dir_all(config_home.join(".claw")).expect("config home should exist");
+    home: PathBuf,
-    fs::create_dir_all(&home).expect("home should exist");
+}
 
+impl HarnessWorkspace {
+    fn new(root: PathBuf) -> Self {
+        Self {
+            config_home: root.join("config-home"),
+            home: root.join("home"),
+            root,
+        }
+    }
+
+    fn create(&self) -> std::io::Result<()> {
+        fs::create_dir_all(&self.root)?;
+        fs::create_dir_all(&self.config_home)?;
+        fs::create_dir_all(&self.home)?;
+        Ok(())
+    }
+}
+
+struct ScenarioRun {
+    response: Value,
+    stdout: String,
+}
+
+#[derive(Debug, Clone)]
+struct ScenarioManifestEntry {
+    name: String,
+    category: String,
+    description: String,
+    parity_refs: Vec<String>,
+}
+
+#[derive(Debug)]
+struct ScenarioReport {
+    name: String,
+    category: String,
+    description: String,
+    parity_refs: Vec<String>,
+    iterations: u64,
+    request_count: usize,
+    tool_uses: Vec<String>,
+    tool_error_count: usize,
+    final_message: String,
+}
+
+fn run_case(case: ScenarioCase, workspace: &HarnessWorkspace, base_url: &str) -> ScenarioRun {
     let mut command = Command::new(env!("CARGO_BIN_EXE_claw"));
     command
-        .current_dir(workspace)
+        .current_dir(&workspace.root)
         .env_clear()
         .env("ANTHROPIC_API_KEY", "test-parity-key")
         .env("ANTHROPIC_BASE_URL", base_url)
-        .env("CLAW_CONFIG_HOME", &config_home)
+        .env("CLAW_CONFIG_HOME", &workspace.config_home)
-        .env("HOME", &home)
+        .env("HOME", &workspace.home)
         .env("NO_COLOR", "1")
+        .env("PATH", "/usr/bin:/bin")
         .args([
             "--model",
             "sonnet",
@@ -132,107 +280,453 @@ fn run_case(case: ScenarioCase, workspace: &Path, base_url: &str) -> Value {
     }
 
     let prompt = format!("{SCENARIO_PREFIX}{}", case.name);
-    let output = command.arg(prompt).output().expect("claw should launch");
+    command.arg(prompt);
+
+    let output = if let Some(stdin) = case.stdin {
+        let mut child = command
+            .stdin(Stdio::piped())
+            .stdout(Stdio::piped())
+            .stderr(Stdio::piped())
+            .spawn()
+            .expect("claw should launch");
+        child
+            .stdin
+            .as_mut()
+            .expect("stdin should be piped")
+            .write_all(stdin.as_bytes())
+            .expect("stdin should write");
+        child.wait_with_output().expect("claw should finish")
+    } else {
+        command.output().expect("claw should launch")
+    };
+
     assert_success(&output);
-    serde_json::from_slice(&output.stdout).expect("prompt output should be valid json")
+    let stdout = String::from_utf8_lossy(&output.stdout).into_owned();
+    ScenarioRun {
+        response: parse_json_output(&stdout),
+        stdout,
+    }
 }
 
-fn seed_noop(_: &Path) {}
+fn prepare_noop(_: &HarnessWorkspace) {}
 
-fn seed_read_fixture(workspace: &Path) {
+fn prepare_read_fixture(workspace: &HarnessWorkspace) {
-    fs::write(workspace.join("fixture.txt"), "alpha parity line\n").expect("fixture should write");
+    fs::write(workspace.root.join("fixture.txt"), "alpha parity line\n")
+        .expect("fixture should write");
 }
 
-fn seed_grep_fixture(workspace: &Path) {
+fn prepare_grep_fixture(workspace: &HarnessWorkspace) {
     fs::write(
-        workspace.join("fixture.txt"),
+        workspace.root.join("fixture.txt"),
         "alpha parity line\nbeta line\ngamma parity line\n",
     )
     .expect("grep fixture should write");
 }
 
-fn assert_streaming_text(_: &Path, response: &Value) {
+fn prepare_multi_tool_fixture(workspace: &HarnessWorkspace) {
-    assert_eq!(
+    fs::write(
-        response["message"],
+        workspace.root.join("fixture.txt"),
-        Value::String("Mock streaming says hello from the parity harness.".to_string())
+        "alpha parity line\nbeta line\ngamma parity line\n",
-    );
+    )
-    assert_eq!(response["iterations"], Value::from(1));
+    .expect("multi tool fixture should write");
-    assert_eq!(response["tool_uses"], Value::Array(Vec::new()));
-    assert_eq!(response["tool_results"], Value::Array(Vec::new()));
 }
 
-fn assert_read_file_roundtrip(workspace: &Path, response: &Value) {
+fn prepare_plugin_fixture(workspace: &HarnessWorkspace) {
-    assert_eq!(response["iterations"], Value::from(2));
+    let plugin_root = workspace
+        .root
+        .join("external-plugins")
+        .join("parity-plugin");
+    let tool_dir = plugin_root.join("tools");
+    let manifest_dir = plugin_root.join(".claude-plugin");
+    fs::create_dir_all(&tool_dir).expect("plugin tools dir");
+    fs::create_dir_all(&manifest_dir).expect("plugin manifest dir");
+
+    let script_path = tool_dir.join("echo-json.sh");
+    fs::write(
+        &script_path,
+        "#!/bin/sh\nINPUT=$(cat)\nprintf '{\"plugin\":\"%s\",\"tool\":\"%s\",\"input\":%s}\\n' \"$CLAWD_PLUGIN_ID\" \"$CLAWD_TOOL_NAME\" \"$INPUT\"\n",
+    )
+    .expect("plugin script should write");
+    let mut permissions = fs::metadata(&script_path)
+        .expect("plugin script metadata")
+        .permissions();
+    permissions.set_mode(0o755);
+    fs::set_permissions(&script_path, permissions).expect("plugin script should be executable");
+
+    fs::write(
+        manifest_dir.join("plugin.json"),
+        r#"{
+  "name": "parity-plugin",
+  "version": "1.0.0",
+  "description": "mock parity plugin",
+  "tools": [
+    {
+      "name": "plugin_echo",
+      "description": "Echo JSON input",
+      "inputSchema": {
+        "type": "object",
+        "properties": {
+          "message": { "type": "string" }
+        },
+        "required": ["message"],
+        "additionalProperties": false
+      },
+      "command": "./tools/echo-json.sh",
+      "requiredPermission": "workspace-write"
+    }
+  ]
+}"#,
+    )
+    .expect("plugin manifest should write");
+
+    fs::write(
+        workspace.config_home.join("settings.json"),
+        json!({
+            "enabledPlugins": {
+                "parity-plugin@external": true
+            },
+            "plugins": {
+                "externalDirectories": [plugin_root.parent().expect("plugin parent").display().to_string()]
+            }
+        })
+        .to_string(),
+    )
+    .expect("plugin settings should write");
+}
+
+fn assert_streaming_text(_: &HarnessWorkspace, run: &ScenarioRun) {
     assert_eq!(
-        response["tool_uses"][0]["name"],
+        run.response["message"],
+        Value::String("Mock streaming says hello from the parity harness.".to_string())
+    );
+    assert_eq!(run.response["iterations"], Value::from(1));
+    assert_eq!(run.response["tool_uses"], Value::Array(Vec::new()));
+    assert_eq!(run.response["tool_results"], Value::Array(Vec::new()));
+}
+
+fn assert_read_file_roundtrip(workspace: &HarnessWorkspace, run: &ScenarioRun) {
+    assert_eq!(run.response["iterations"], Value::from(2));
+    assert_eq!(
+        run.response["tool_uses"][0]["name"],
         Value::String("read_file".to_string())
     );
     assert_eq!(
-        response["tool_uses"][0]["input"],
+        run.response["tool_uses"][0]["input"],
         Value::String(r#"{"path":"fixture.txt"}"#.to_string())
     );
-    assert!(response["message"]
+    assert!(run.response["message"]
         .as_str()
         .expect("message text")
         .contains("alpha parity line"));
-    let output = response["tool_results"][0]["output"]
+    let output = run.response["tool_results"][0]["output"]
         .as_str()
         .expect("tool output");
-    assert!(output.contains(&workspace.join("fixture.txt").display().to_string()));
+    assert!(output.contains(&workspace.root.join("fixture.txt").display().to_string()));
     assert!(output.contains("alpha parity line"));
 }
 
-fn assert_grep_chunk_assembly(_: &Path, response: &Value) {
+fn assert_grep_chunk_assembly(_: &HarnessWorkspace, run: &ScenarioRun) {
-    assert_eq!(response["iterations"], Value::from(2));
+    assert_eq!(run.response["iterations"], Value::from(2));
     assert_eq!(
-        response["tool_uses"][0]["name"],
+        run.response["tool_uses"][0]["name"],
         Value::String("grep_search".to_string())
     );
     assert_eq!(
-        response["tool_uses"][0]["input"],
+        run.response["tool_uses"][0]["input"],
         Value::String(
             r#"{"pattern":"parity","path":"fixture.txt","output_mode":"count"}"#.to_string()
         )
     );
-    assert!(response["message"]
+    assert!(run.response["message"]
         .as_str()
         .expect("message text")
         .contains("2 occurrences"));
-    assert_eq!(response["tool_results"][0]["is_error"], Value::Bool(false));
+    assert_eq!(
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(false)
+    );
 }
 
-fn assert_write_file_allowed(workspace: &Path, response: &Value) {
+fn assert_write_file_allowed(workspace: &HarnessWorkspace, run: &ScenarioRun) {
-    assert_eq!(response["iterations"], Value::from(2));
+    assert_eq!(run.response["iterations"], Value::from(2));
     assert_eq!(
-        response["tool_uses"][0]["name"],
+        run.response["tool_uses"][0]["name"],
         Value::String("write_file".to_string())
     );
-    assert!(response["message"]
+    assert!(run.response["message"]
         .as_str()
         .expect("message text")
         .contains("generated/output.txt"));
-    let generated = workspace.join("generated").join("output.txt");
+    let generated = workspace.root.join("generated").join("output.txt");
     let contents = fs::read_to_string(&generated).expect("generated file should exist");
     assert_eq!(contents, "created by mock service\n");
-    assert_eq!(response["tool_results"][0]["is_error"], Value::Bool(false));
+    assert_eq!(
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(false)
+    );
 }
 
-fn assert_write_file_denied(workspace: &Path, response: &Value) {
+fn assert_write_file_denied(workspace: &HarnessWorkspace, run: &ScenarioRun) {
-    assert_eq!(response["iterations"], Value::from(2));
+    assert_eq!(run.response["iterations"], Value::from(2));
     assert_eq!(
-        response["tool_uses"][0]["name"],
+        run.response["tool_uses"][0]["name"],
         Value::String("write_file".to_string())
     );
-    let tool_output = response["tool_results"][0]["output"]
+    let tool_output = run.response["tool_results"][0]["output"]
         .as_str()
         .expect("tool output");
     assert!(tool_output.contains("requires workspace-write permission"));
-    assert_eq!(response["tool_results"][0]["is_error"], Value::Bool(true));
+    assert_eq!(
-    assert!(response["message"]
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(true)
+    );
+    assert!(run.response["message"]
         .as_str()
         .expect("message text")
         .contains("denied as expected"));
-    assert!(!workspace.join("generated").join("denied.txt").exists());
+    assert!(!workspace.root.join("generated").join("denied.txt").exists());
+}
+
+fn assert_multi_tool_turn_roundtrip(_: &HarnessWorkspace, run: &ScenarioRun) {
+    assert_eq!(run.response["iterations"], Value::from(2));
+    let tool_uses = run.response["tool_uses"]
+        .as_array()
+        .expect("tool uses array");
+    assert_eq!(
+        tool_uses.len(),
+        2,
+        "expected two tool uses in a single turn"
+    );
+    assert_eq!(tool_uses[0]["name"], Value::String("read_file".to_string()));
+    assert_eq!(
+        tool_uses[1]["name"],
+        Value::String("grep_search".to_string())
+    );
+    let tool_results = run.response["tool_results"]
+        .as_array()
+        .expect("tool results array");
+    assert_eq!(
+        tool_results.len(),
+        2,
+        "expected two tool results in a single turn"
+    );
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("alpha parity line"));
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("2 occurrences"));
+}
+
+fn assert_bash_stdout_roundtrip(_: &HarnessWorkspace, run: &ScenarioRun) {
+    assert_eq!(run.response["iterations"], Value::from(2));
+    assert_eq!(
+        run.response["tool_uses"][0]["name"],
+        Value::String("bash".to_string())
+    );
+    let tool_output = run.response["tool_results"][0]["output"]
+        .as_str()
+        .expect("tool output");
+    let parsed: Value = serde_json::from_str(tool_output).expect("bash output json");
+    assert_eq!(
+        parsed["stdout"],
+        Value::String("alpha from bash".to_string())
+    );
+    assert_eq!(
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(false)
+    );
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("alpha from bash"));
+}
+
+fn assert_bash_permission_prompt_approved(_: &HarnessWorkspace, run: &ScenarioRun) {
+    assert!(run.stdout.contains("Permission approval required"));
+    assert!(run.stdout.contains("Approve this tool call? [y/N]:"));
+    assert_eq!(run.response["iterations"], Value::from(2));
+    assert_eq!(
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(false)
+    );
+    let tool_output = run.response["tool_results"][0]["output"]
+        .as_str()
+        .expect("tool output");
+    let parsed: Value = serde_json::from_str(tool_output).expect("bash output json");
+    assert_eq!(
+        parsed["stdout"],
+        Value::String("approved via prompt".to_string())
+    );
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("approved and executed"));
+}
+
+fn assert_bash_permission_prompt_denied(_: &HarnessWorkspace, run: &ScenarioRun) {
+    assert!(run.stdout.contains("Permission approval required"));
+    assert!(run.stdout.contains("Approve this tool call? [y/N]:"));
+    assert_eq!(run.response["iterations"], Value::from(2));
+    let tool_output = run.response["tool_results"][0]["output"]
+        .as_str()
+        .expect("tool output");
+    assert!(tool_output.contains("denied by user approval prompt"));
+    assert_eq!(
+        run.response["tool_results"][0]["is_error"],
+        Value::Bool(true)
+    );
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("denied as expected"));
+}
+
+fn assert_plugin_tool_roundtrip(_: &HarnessWorkspace, run: &ScenarioRun) {
+    assert_eq!(run.response["iterations"], Value::from(2));
+    assert_eq!(
+        run.response["tool_uses"][0]["name"],
+        Value::String("plugin_echo".to_string())
+    );
+    let tool_output = run.response["tool_results"][0]["output"]
+        .as_str()
+        .expect("tool output");
+    let parsed: Value = serde_json::from_str(tool_output).expect("plugin output json");
+    assert_eq!(
+        parsed["plugin"],
+        Value::String("parity-plugin@external".to_string())
+    );
+    assert_eq!(parsed["tool"], Value::String("plugin_echo".to_string()));
+    assert_eq!(
+        parsed["input"]["message"],
+        Value::String("hello from plugin parity".to_string())
+    );
+    assert!(run.response["message"]
+        .as_str()
+        .expect("message text")
+        .contains("hello from plugin parity"));
+}
+
+fn parse_json_output(stdout: &str) -> Value {
+    if let Some(index) = stdout.rfind("{\"auto_compaction\"") {
+        return serde_json::from_str(&stdout[index..]).unwrap_or_else(|error| {
+            panic!("failed to parse JSON response from stdout: {error}\n{stdout}")
+        });
+    }
+
+    stdout
+        .lines()
+        .rev()
+        .find_map(|line| {
+            let trimmed = line.trim();
+            if trimmed.starts_with('{') && trimmed.ends_with('}') {
+                serde_json::from_str(trimmed).ok()
+            } else {
+                None
+            }
+        })
+        .unwrap_or_else(|| panic!("no JSON response line found in stdout:\n{stdout}"))
+}
+
+fn build_scenario_report(
+    name: &str,
+    manifest_entry: &ScenarioManifestEntry,
+    response: &Value,
+) -> ScenarioReport {
+    ScenarioReport {
+        name: name.to_string(),
+        category: manifest_entry.category.clone(),
+        description: manifest_entry.description.clone(),
+        parity_refs: manifest_entry.parity_refs.clone(),
+        iterations: response["iterations"]
+            .as_u64()
+            .expect("iterations should exist"),
+        request_count: 0,
+        tool_uses: response["tool_uses"]
+            .as_array()
+            .expect("tool uses array")
+            .iter()
+            .filter_map(|value| value["name"].as_str().map(ToOwned::to_owned))
+            .collect(),
+        tool_error_count: response["tool_results"]
+            .as_array()
+            .expect("tool results array")
+            .iter()
+            .filter(|value| value["is_error"].as_bool().unwrap_or(false))
+            .count(),
+        final_message: response["message"]
+            .as_str()
+            .expect("message text")
+            .to_string(),
+    }
+}
+
+fn maybe_write_report(reports: &[ScenarioReport]) {
+    let Some(path) = std::env::var_os("MOCK_PARITY_REPORT_PATH") else {
+        return;
+    };
+
+    let payload = json!({
+        "scenario_count": reports.len(),
+        "request_count": reports.iter().map(|report| report.request_count).sum::<usize>(),
+        "scenarios": reports.iter().map(scenario_report_json).collect::<Vec<_>>(),
+    });
+    fs::write(
+        path,
+        serde_json::to_vec_pretty(&payload).expect("report json should serialize"),
+    )
+    .expect("report should write");
+}
+
+fn load_scenario_manifest() -> Vec<ScenarioManifestEntry> {
+    let manifest_path =
+        Path::new(env!("CARGO_MANIFEST_DIR")).join("../../mock_parity_scenarios.json");
+    let manifest = fs::read_to_string(&manifest_path).expect("scenario manifest should exist");
+    serde_json::from_str::<Vec<Value>>(&manifest)
+        .expect("scenario manifest should parse")
+        .into_iter()
+        .map(|entry| ScenarioManifestEntry {
+            name: entry["name"]
+                .as_str()
+                .expect("scenario name should be a string")
+                .to_string(),
+            category: entry["category"]
+                .as_str()
+                .expect("scenario category should be a string")
+                .to_string(),
+            description: entry["description"]
+                .as_str()
+                .expect("scenario description should be a string")
+                .to_string(),
+            parity_refs: entry["parity_refs"]
+                .as_array()
+                .expect("parity refs should be an array")
+                .iter()
+                .map(|value| {
+                    value
+                        .as_str()
+                        .expect("parity ref should be a string")
+                        .to_string()
+                })
+                .collect(),
+        })
+        .collect()
+}
+
+fn scenario_report_json(report: &ScenarioReport) -> Value {
+    json!({
+        "name": report.name,
+        "category": report.category,
+        "description": report.description,
+        "parity_refs": report.parity_refs,
+        "iterations": report.iterations,
+        "request_count": report.request_count,
+        "tool_uses": report.tool_uses,
+        "tool_error_count": report.tool_error_count,
+        "final_message": report.final_message,
+    })
 }
 
 fn assert_success(output: &Output) {

rust/mock_parity_scenarios.json

@@ -0,0 +1,92 @@
+[
+  {
+    "name": "streaming_text",
+    "category": "baseline",
+    "description": "Validates streamed assistant text with no tool calls.",
+    "parity_refs": [
+      "Mock parity harness — milestone 1",
+      "Streaming response support validated by the mock parity harness"
+    ]
+  },
+  {
+    "name": "read_file_roundtrip",
+    "category": "file-tools",
+    "description": "Exercises read_file tool execution and final assistant synthesis.",
+    "parity_refs": [
+      "Mock parity harness — milestone 1",
+      "File tools — harness-validated flows"
+    ]
+  },
+  {
+    "name": "grep_chunk_assembly",
+    "category": "file-tools",
+    "description": "Validates grep_search partial JSON chunk assembly and follow-up synthesis.",
+    "parity_refs": [
+      "Mock parity harness — milestone 1",
+      "File tools — harness-validated flows"
+    ]
+  },
+  {
+    "name": "write_file_allowed",
+    "category": "file-tools",
+    "description": "Confirms workspace-write write_file success and filesystem side effects.",
+    "parity_refs": [
+      "Mock parity harness — milestone 1",
+      "File tools — harness-validated flows"
+    ]
+  },
+  {
+    "name": "write_file_denied",
+    "category": "permissions",
+    "description": "Confirms read-only mode blocks write_file with an error result.",
+    "parity_refs": [
+      "Mock parity harness — milestone 1",
+      "Permission enforcement across tool paths"
+    ]
+  },
+  {
+    "name": "multi_tool_turn_roundtrip",
+    "category": "multi-tool-turns",
+    "description": "Executes read_file and grep_search in the same assistant turn before the final reply.",
+    "parity_refs": [
+      "Mock parity harness — milestone 2 (behavioral expansion)",
+      "Multi-tool assistant turns"
+    ]
+  },
+  {
+    "name": "bash_stdout_roundtrip",
+    "category": "bash",
+    "description": "Validates bash execution and stdout roundtrip in danger-full-access mode.",
+    "parity_refs": [
+      "Mock parity harness — milestone 2 (behavioral expansion)",
+      "Bash tool — upstream has 18 submodules, Rust has 1:"
+    ]
+  },
+  {
+    "name": "bash_permission_prompt_approved",
+    "category": "permissions",
+    "description": "Exercises workspace-write to bash escalation with a positive approval response.",
+    "parity_refs": [
+      "Mock parity harness — milestone 2 (behavioral expansion)",
+      "Permission enforcement across tool paths"
+    ]
+  },
+  {
+    "name": "bash_permission_prompt_denied",
+    "category": "permissions",
+    "description": "Exercises workspace-write to bash escalation with a denied approval response.",
+    "parity_refs": [
+      "Mock parity harness — milestone 2 (behavioral expansion)",
+      "Permission enforcement across tool paths"
+    ]
+  },
+  {
+    "name": "plugin_tool_roundtrip",
+    "category": "plugin-paths",
+    "description": "Loads an external plugin tool and executes it through the runtime tool registry.",
+    "parity_refs": [
+      "Mock parity harness — milestone 2 (behavioral expansion)",
+      "Plugin tool execution path"
+    ]
+  }
+]

rust/scripts/run_mock_parity_diff.py

@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+import json
+import os
+import subprocess
+import sys
+import tempfile
+from collections import defaultdict
+from pathlib import Path
+
+
+def load_manifest(path: Path) -> list[dict]:
+    return json.loads(path.read_text())
+
+
+def load_parity_text(path: Path) -> str:
+    return path.read_text()
+
+
+def ensure_refs_exist(manifest: list[dict], parity_text: str) -> list[tuple[str, str]]:
+    missing: list[tuple[str, str]] = []
+    for entry in manifest:
+        for ref in entry.get("parity_refs", []):
+            if ref not in parity_text:
+                missing.append((entry["name"], ref))
+    return missing
+
+
+def run_harness(rust_root: Path) -> dict:
+    with tempfile.TemporaryDirectory(prefix="mock-parity-report-") as temp_dir:
+        report_path = Path(temp_dir) / "report.json"
+        env = os.environ.copy()
+        env["MOCK_PARITY_REPORT_PATH"] = str(report_path)
+        subprocess.run(
+            [
+                "cargo",
+                "test",
+                "-p",
+                "rusty-claude-cli",
+                "--test",
+                "mock_parity_harness",
+                "--",
+                "--nocapture",
+            ],
+            cwd=rust_root,
+            check=True,
+            env=env,
+        )
+        return json.loads(report_path.read_text())
+
+
+def main() -> int:
+    script_path = Path(__file__).resolve()
+    rust_root = script_path.parent.parent
+    repo_root = rust_root.parent
+    manifest = load_manifest(rust_root / "mock_parity_scenarios.json")
+    parity_text = load_parity_text(repo_root / "PARITY.md")
+
+    missing_refs = ensure_refs_exist(manifest, parity_text)
+    if missing_refs:
+        print("Missing PARITY.md references:", file=sys.stderr)
+        for scenario_name, ref in missing_refs:
+            print(f"  - {scenario_name}: {ref}", file=sys.stderr)
+        return 1
+
+    should_run = "--no-run" not in sys.argv[1:]
+    report = run_harness(rust_root) if should_run else None
+    report_by_name = {
+        entry["name"]: entry for entry in report.get("scenarios", [])
+    } if report else {}
+
+    print("Mock parity diff checklist")
+    print(f"Repo root: {repo_root}")
+    print(f"Scenario manifest: {rust_root / 'mock_parity_scenarios.json'}")
+    print(f"PARITY source: {repo_root / 'PARITY.md'}")
+    print()
+
+    for entry in manifest:
+        scenario_name = entry["name"]
+        scenario_report = report_by_name.get(scenario_name)
+        status = "PASS" if scenario_report else ("MAPPED" if not should_run else "MISSING")
+        print(f"[{status}] {scenario_name} ({entry['category']})")
+        print(f"  description: {entry['description']}")
+        print(f"  parity refs: {' | '.join(entry['parity_refs'])}")
+        if scenario_report:
+            print(
+                "  result: iterations={iterations} requests={requests} tool_uses={tool_uses} tool_errors={tool_errors}".format(
+                    iterations=scenario_report["iterations"],
+                    requests=scenario_report["request_count"],
+                    tool_uses=", ".join(scenario_report["tool_uses"]) or "none",
+                    tool_errors=scenario_report["tool_error_count"],
+                )
+            )
+            print(f"  final: {scenario_report['final_message']}")
+        print()
+
+    coverage = defaultdict(list)
+    for entry in manifest:
+        for ref in entry["parity_refs"]:
+            coverage[ref].append(entry["name"])
+
+    print("PARITY coverage map")
+    for ref, scenarios in coverage.items():
+        print(f"- {ref}")
+        print(f"  scenarios: {', '.join(scenarios)}")
+
+    if report and report.get("scenarios"):
+        first = report["scenarios"][0]
+        print()
+        print("First scenario result")
+        print(f"- name: {first['name']}")
+        print(f"- iterations: {first['iterations']}")
+        print(f"- requests: {first['request_count']}")
+        print(f"- tool_uses: {', '.join(first['tool_uses']) or 'none'}")
+        print(f"- tool_errors: {first['tool_error_count']}")
+        print(f"- final_message: {first['final_message']}")
+        print()
+        print(
+            "Harness summary: {scenario_count} scenarios, {request_count} requests".format(
+                scenario_count=report["scenario_count"],
+                request_count=report["request_count"],
+            )
+        )
+
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())