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+# Parity Status — claw-code Rust Port
+
+Last updated: 2026-04-03
+
+## Mock parity harness — milestone 1
+
+- [x] Deterministic Anthropic-compatible mock service (`rust/crates/mock-anthropic-service`)
+- [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)
+
+| Tool | Rust Impl | Behavioral Notes |
+|------|-----------|-----------------|
+| **bash** | `runtime::bash` 283 LOC | subprocess exec, timeout, background, sandbox — **strong parity**. Missing: sedValidation, pathValidation, readOnlyValidation, destructiveCommandWarning, commandSemantics (upstream has 18 submodules for bash alone) |
+| **read_file** | `runtime::file_ops` | offset/limit read — **good parity** |
+| **write_file** | `runtime::file_ops` | file create/overwrite — **good parity** |
+| **edit_file** | `runtime::file_ops` | old/new string replacement — **good parity**. Missing: replace_all was recently added |
+| **glob_search** | `runtime::file_ops` | glob pattern matching — **good parity** |
+| **grep_search** | `runtime::file_ops` | ripgrep-style search — **good parity** |
+| **WebFetch** | `tools` | URL fetch + content extraction — **moderate parity** (need to verify content truncation, redirect handling vs upstream) |
+| **WebSearch** | `tools` | search query execution — **moderate parity** |
+| **TodoWrite** | `tools` | todo/note persistence — **moderate parity** |
+| **Skill** | `tools` | skill discovery/install — **moderate parity** |
+| **Agent** | `tools` | agent delegation — **moderate parity** |
+| **ToolSearch** | `tools` | tool discovery — **good parity** |
+| **NotebookEdit** | `tools` | jupyter notebook cell editing — **moderate parity** |
+| **Sleep** | `tools` | delay execution — **good parity** |
+| **SendUserMessage/Brief** | `tools` | user-facing message — **good parity** |
+| **Config** | `tools` | config inspection — **moderate parity** |
+| **EnterPlanMode** | `tools` | worktree plan mode toggle — **good parity** |
+| **ExitPlanMode** | `tools` | worktree plan mode restore — **good parity** |
+| **StructuredOutput** | `tools` | passthrough JSON — **good parity** |
+| **REPL** | `tools` | subprocess code execution — **moderate parity** |
+| **PowerShell** | `tools` | Windows PowerShell execution — **moderate parity** |
+
+### Stubs Only (surface parity, no behavior)
+
+| Tool | Status | Notes |
+|------|--------|-------|
+| **AskUserQuestion** | stub | needs user I/O integration |
+| **TaskCreate** | stub | needs sub-agent runtime |
+| **TaskGet** | stub | needs task registry |
+| **TaskList** | stub | needs task registry |
+| **TaskStop** | stub | needs process management |
+| **TaskUpdate** | stub | needs task message passing |
+| **TaskOutput** | stub | needs output capture |
+| **TeamCreate** | stub | needs parallel task orchestration |
+| **TeamDelete** | stub | needs team lifecycle |
+| **CronCreate** | stub | needs scheduler runtime |
+| **CronDelete** | stub | needs cron registry |
+| **CronList** | stub | needs cron registry |
+| **LSP** | stub | needs language server client |
+| **ListMcpResources** | stub | needs MCP client |
+| **ReadMcpResource** | stub | needs MCP client |
+| **McpAuth** | stub | needs OAuth flow |
+| **MCP** | stub | needs MCP tool proxy |
+| **RemoteTrigger** | stub | needs HTTP client |
+| **TestingPermission** | stub | test-only, low priority |
+
+## Slash Commands: 67/141 upstream entries
+
+- 27 original specs (pre-today) — all with real handlers
+- 40 new specs — parse + stub handler ("not yet implemented")
+- Remaining ~74 upstream entries are internal modules/dialogs/steps, not user `/commands`
+
+### Missing Behavioral Features (in existing real tools)
+
+**Bash tool — upstream has 18 submodules, Rust has 1:**
+- [x] `sedValidation` — validate sed commands before execution
+- [x] `pathValidation` — validate file paths in commands
+- [x] `readOnlyValidation` — block writes in read-only mode
+- [x] `destructiveCommandWarning` — warn on rm -rf, etc.
+- [x] `commandSemantics` — classify command intent
+- [x] `bashPermissions` — permission gating per command type
+- [x] `bashSecurity` — security checks
+- [x] `modeValidation` — validate against current permission mode
+- [x] `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:**
+- [x] Path traversal prevention (symlink following, ../ escapes)
+- [x] Size limits on read/write
+- [x] 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)
+- [ ] Output truncation (large stdout/file content)
+- [ ] Session compaction behavior matching
+- [ ] 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
+- [ ] No `#[ignore]` tests hiding failures (only 1 allowed: `live_stream_smoke_test`)
+- [ ] CI green on every commit
+- [ ] Codebase shape clean for handoff