# PARITY GAP ANALYSIS Scope: read-only comparison between the original TypeScript source at `/home/bellman/Workspace/claude-code/src/` and the Rust port under `rust/crates/`. Method: compared feature surfaces, registries, entrypoints, and runtime plumbing only. No TypeScript source was copied. ## Executive summary The Rust port has a good foundation for: - Anthropic API/OAuth basics - local conversation/session state - a core tool loop - MCP stdio/bootstrap support - CLAUDE.md discovery - a small but usable built-in tool set It is **not feature-parity** with the TypeScript CLI. Largest gaps: - **plugins** are effectively absent in Rust - **hooks** are parsed but not executed in Rust - **CLI breadth** is much narrower in Rust - **skills** are local-file only in Rust, without the TS registry/bundled pipeline - **assistant orchestration** lacks TS hook-aware orchestration and remote/structured transports - **services** beyond core API/OAuth/MCP are mostly missing in Rust --- ## tools/ ### TS exists Evidence: - `src/tools/` contains broad tool families including `AgentTool`, `AskUserQuestionTool`, `BashTool`, `ConfigTool`, `FileReadTool`, `FileWriteTool`, `GlobTool`, `GrepTool`, `LSPTool`, `ListMcpResourcesTool`, `MCPTool`, `McpAuthTool`, `ReadMcpResourceTool`, `RemoteTriggerTool`, `ScheduleCronTool`, `SkillTool`, `Task*`, `Team*`, `TodoWriteTool`, `ToolSearchTool`, `WebFetchTool`, `WebSearchTool`. - Tool execution/orchestration is split across `src/services/tools/StreamingToolExecutor.ts`, `src/services/tools/toolExecution.ts`, `src/services/tools/toolHooks.ts`, and `src/services/tools/toolOrchestration.ts`. ### Rust exists Evidence: - Tool registry is centralized in `rust/crates/tools/src/lib.rs` via `mvp_tool_specs()`. - Current built-ins include shell/file/search/web/todo/skill/agent/config/notebook/repl/powershell primitives. - Runtime execution is wired through `rust/crates/tools/src/lib.rs` and `rust/crates/runtime/src/conversation.rs`. ### Missing or broken in Rust - No Rust equivalents for major TS tools such as `AskUserQuestionTool`, `LSPTool`, `ListMcpResourcesTool`, `MCPTool`, `McpAuthTool`, `ReadMcpResourceTool`, `RemoteTriggerTool`, `ScheduleCronTool`, `Task*`, `Team*`, and several workflow/system tools. - Rust tool surface is still explicitly an MVP registry, not a parity registry. - Rust lacks TS’s layered tool orchestration split. **Status:** partial core only. --- ## hooks/ ### TS exists Evidence: - Hook command surface under `src/commands/hooks/`. - Runtime hook machinery in `src/services/tools/toolHooks.ts` and `src/services/tools/toolExecution.ts`. - TS supports `PreToolUse`, `PostToolUse`, and broader hook-driven behaviors configured through settings and documented in `src/skills/bundled/updateConfig.ts`. ### Rust exists Evidence: - Hook config is parsed and merged in `rust/crates/runtime/src/config.rs`. - Hook config can be inspected via Rust config reporting in `rust/crates/commands/src/lib.rs` and `rust/crates/rusty-claude-cli/src/main.rs`. - Prompt guidance mentions hooks in `rust/crates/runtime/src/prompt.rs`. ### Missing or broken in Rust - No actual hook execution pipeline in `rust/crates/runtime/src/conversation.rs`. - No PreToolUse/PostToolUse mutation/deny/rewrite/result-hook behavior. - No Rust `/hooks` parity command. **Status:** config-only; runtime behavior missing. --- ## plugins/ ### TS exists Evidence: - Built-in plugin scaffolding in `src/plugins/builtinPlugins.ts` and `src/plugins/bundled/index.ts`. - Plugin lifecycle/services in `src/services/plugins/PluginInstallationManager.ts` and `src/services/plugins/pluginOperations.ts`. - CLI/plugin command surface under `src/commands/plugin/` and `src/commands/reload-plugins/`. ### Rust exists Evidence: - No dedicated plugin subsystem appears under `rust/crates/`. - Repo-wide Rust references to plugins are effectively absent beyond text/help mentions. ### Missing or broken in Rust - No plugin loader. - No marketplace install/update/enable/disable flow. - No `/plugin` or `/reload-plugins` parity. - No plugin-provided hook/tool/command/MCP extension path. **Status:** missing. --- ## skills/ and CLAUDE.md discovery ### TS exists Evidence: - Skill loading/registry pipeline in `src/skills/loadSkillsDir.ts`, `src/skills/bundledSkills.ts`, and `src/skills/mcpSkillBuilders.ts`. - Bundled skills under `src/skills/bundled/`. - Skills command surface under `src/commands/skills/`. ### Rust exists Evidence: - `Skill` tool in `rust/crates/tools/src/lib.rs` resolves and reads local `SKILL.md` files. - CLAUDE.md discovery is implemented in `rust/crates/runtime/src/prompt.rs`. - Rust supports `/memory` and `/init` via `rust/crates/commands/src/lib.rs` and `rust/crates/rusty-claude-cli/src/main.rs`. ### Missing or broken in Rust - No bundled skill registry equivalent. - No `/skills` command. - No MCP skill-builder pipeline. - No TS-style live skill discovery/reload/change handling. - No comparable session-memory / team-memory integration around skills. **Status:** basic local skill loading only. --- ## cli/ ### TS exists Evidence: - Large command surface under `src/commands/` including `agents`, `hooks`, `mcp`, `memory`, `model`, `permissions`, `plan`, `plugin`, `resume`, `review`, `skills`, `tasks`, and many more. - Structured/remote transport stack in `src/cli/structuredIO.ts`, `src/cli/remoteIO.ts`, and `src/cli/transports/*`. - CLI handler split in `src/cli/handlers/*`. ### Rust exists Evidence: - Shared slash command registry in `rust/crates/commands/src/lib.rs`. - Rust slash commands currently cover `help`, `status`, `compact`, `model`, `permissions`, `clear`, `cost`, `resume`, `config`, `memory`, `init`, `diff`, `version`, `export`, `session`. - Main CLI/repl/prompt handling lives in `rust/crates/rusty-claude-cli/src/main.rs`. ### Missing or broken in Rust - Missing major TS command families: `/agents`, `/hooks`, `/mcp`, `/plugin`, `/skills`, `/plan`, `/review`, `/tasks`, and many others. - No Rust equivalent to TS structured IO / remote transport layers. - No TS-style handler decomposition for auth/plugins/MCP/agents. - JSON prompt mode is improved on this branch, but still not clean transport parity: empirical verification shows tool-capable JSON output can emit human-readable tool-result lines before the final JSON object. **Status:** functional local CLI core, much narrower than TS. --- ## assistant/ (agentic loop, streaming, tool calling) ### TS exists Evidence: - Assistant/session surface at `src/assistant/sessionHistory.ts`. - Tool orchestration in `src/services/tools/StreamingToolExecutor.ts`, `src/services/tools/toolExecution.ts`, `src/services/tools/toolOrchestration.ts`. - Remote/structured streaming layers in `src/cli/structuredIO.ts` and `src/cli/remoteIO.ts`. ### Rust exists Evidence: - Core loop in `rust/crates/runtime/src/conversation.rs`. - Stream/tool event translation in `rust/crates/rusty-claude-cli/src/main.rs`. - Session persistence in `rust/crates/runtime/src/session.rs`. ### Missing or broken in Rust - No TS-style hook-aware orchestration layer. - No TS structured/remote assistant transport stack. - No richer TS assistant/session-history/background-task integration. - JSON output path is no longer single-turn only on this branch, but output cleanliness still lags TS transport expectations. **Status:** strong core loop, missing orchestration layers. --- ## services/ (API client, auth, models, MCP) ### TS exists Evidence: - API services under `src/services/api/*`. - OAuth services under `src/services/oauth/*`. - MCP services under `src/services/mcp/*`. - Additional service layers for analytics, prompt suggestion, session memory, plugin operations, settings sync, policy limits, team memory sync, notifier, voice, and more under `src/services/*`. ### Rust exists Evidence: - Core Anthropic API client in `rust/crates/api/src/{client,error,sse,types}.rs`. - OAuth support in `rust/crates/runtime/src/oauth.rs`. - MCP config/bootstrap/client support in `rust/crates/runtime/src/{config,mcp,mcp_client,mcp_stdio}.rs`. - Usage accounting in `rust/crates/runtime/src/usage.rs`. - Remote upstream-proxy support in `rust/crates/runtime/src/remote.rs`. ### Missing or broken in Rust - Most TS service ecosystem beyond core messaging/auth/MCP is absent. - No TS-equivalent plugin service layer. - No TS-equivalent analytics/settings-sync/policy-limit/team-memory subsystems. - No TS-style MCP connection-manager/UI layer. - Model/provider ergonomics remain thinner than TS. **Status:** core foundation exists; broader service ecosystem missing. --- ## Critical bug status in this worktree ### Fixed - **Prompt mode tools enabled** - `rust/crates/rusty-claude-cli/src/main.rs` now constructs prompt mode with `LiveCli::new(model, true, ...)`. - **Default permission mode = DangerFullAccess** - Runtime default now resolves to `DangerFullAccess` in `rust/crates/rusty-claude-cli/src/main.rs`. - Clap default also uses `DangerFullAccess` in `rust/crates/rusty-claude-cli/src/args.rs`. - Init template writes `dontAsk` in `rust/crates/rusty-claude-cli/src/init.rs`. - **Streaming `{}` tool-input prefix bug** - `rust/crates/rusty-claude-cli/src/main.rs` now strips the initial empty object only for streaming tool input, while preserving legitimate `{}` in non-stream responses. - **Unlimited max_iterations** - Verified at `rust/crates/runtime/src/conversation.rs` with `usize::MAX`. ### Remaining notable parity issue - **JSON prompt output cleanliness** - Tool-capable JSON mode now loops, but empirical verification still shows pre-JSON human-readable tool-result output when tools fire.