claw-code/rust

🦞 Claw Code — Rust Implementation

A high-performance Rust rewrite of the Claw Code CLI agent harness. Built for speed, safety, and native tool execution.

For a task-oriented guide with copy/paste examples, see ../USAGE.md.

Quick Start

# Inspect available commands
cd rust/
cargo run -p rusty-claude-cli -- --help

# Build the workspace
cargo build --workspace

# Run the interactive REPL
cargo run -p rusty-claude-cli -- --model claude-opus-4-7

# One-shot prompt
cargo run -p rusty-claude-cli -- prompt "explain this codebase"

# JSON output for automation
cargo run -p rusty-claude-cli -- --output-format json prompt "summarize src/main.rs"

Configuration

Set your API credentials:

export ANTHROPIC_API_KEY="sk-ant-..."
# Or use a proxy
export ANTHROPIC_BASE_URL="https://your-proxy.com"

Or provide an OAuth bearer token directly:

export ANTHROPIC_AUTH_TOKEN="anthropic-oauth-or-proxy-bearer-token"

Local models via Ollama (WSL)

Claw works with any OpenAI-compatible endpoint, including a local Ollama server. This is handy for offline use or for driving the CLI from WSL against models served on the Windows host.

cd rust/

# 1. Build the release binary
cargo build --release

# 2. Point claw at the local Ollama OpenAI-compatible endpoint
export OPENAI_BASE_URL="http://127.0.0.1:11434/v1"
export OPENAI_API_KEY="ollama"   # any non-empty value works; Ollama ignores it

# 3. Run. Prefix the model with `openai/` so prefix routing selects the
#    OpenAI-compatible provider, and use the exact Ollama tag.
./target/release/claw --model openai/qwen3.5:9b

The model name must match the Ollama tag exactly. Ollama tags use a colon (name:tag), e.g. qwen3.5:9b — not a hyphen (qwen3.5-9b), which the server rejects with 404 ... model not found. In the command above the openai/ prefix is what selects the OpenAI-compatible provider (the prefix is stripped before the tag is sent to Ollama). You can also drop the prefix and pass the bare tag — when OPENAI_BASE_URL is set, claw routes a prefix-less model to the OpenAI-compatible endpoint as long as the name contains a : or .. Either way, always pass the full colon tag. List the installed tags with:

ollama list                                 # native view
curl -s http://127.0.0.1:11434/v1/models    # OpenAI-compatible view

WSL note: when Ollama runs on the Windows host, WSL 2 forwards 127.0.0.1:11434 automatically. If the connection is refused, start Ollama on the host (ollama serve) or point OPENAI_BASE_URL at the host IP instead of 127.0.0.1.

Reasoning ("thinking") models such as Qwen3 are supported. Ollama streams the chain-of-thought in a reasoning field with an empty content; claw surfaces it as a separate thinking block so both the reasoning trace and the final answer are rendered.

Mock parity harness

The workspace now includes a deterministic Anthropic-compatible mock service and a clean-environment CLI harness for end-to-end parity checks.

cd rust/

# Run the scripted clean-environment harness
./scripts/run_mock_parity_harness.sh

# Or start the mock service manually for ad hoc CLI runs
cargo run -p mock-anthropic-service -- --bind 127.0.0.1:0

Harness coverage:

• streaming_text
• read_file_roundtrip
• 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

Feature	Status
Anthropic / OpenAI-compatible provider flows + streaming	✅
Direct bearer-token auth via ANTHROPIC_AUTH_TOKEN	✅
Interactive REPL (rustyline)	✅
Tool system (bash, read, write, edit, grep, glob)	✅
Web tools (search, fetch)	✅
Sub-agent / agent surfaces	✅
Todo tracking	✅
Notebook editing	✅
CLAUDE.md / CLAW.md / AGENTS.md project memory	✅
Config file hierarchy (.claw.json + merged config sections)	✅
Permission system	✅
MCP server lifecycle + inspection	✅
Session persistence + resume	✅
Cost / usage / stats surfaces	✅
Git integration	✅
Markdown terminal rendering (ANSI)	✅
Model aliases (opus/sonnet/haiku)	✅
Direct CLI subcommands (status, sandbox, agents, mcp, skills, doctor)	✅
Slash commands (including /skills, /agents, /mcp, /doctor, /plugin, /subagent)	✅
Hooks (/hooks, config-backed lifecycle hooks)	✅
Plugin management surfaces	✅
Skills inventory / install / uninstall surfaces	✅
Machine-readable JSON output across core CLI surfaces	✅

Model Aliases

Short names resolve to the latest model versions:

Alias	Resolves To
opus	claude-opus-4-7
sonnet	claude-sonnet-4-6
haiku	claude-haiku-4-5-20251213

CLI Flags and Commands

Representative current surface:

claw [OPTIONS] [COMMAND]

Flags:
  --model MODEL
  --output-format text|json  (case-insensitive; CLAW_OUTPUT_FORMAT supplies the default, flags override env)
  --permission-mode MODE
  --cwd PATH, -C PATH, --directory PATH
  --dangerously-skip-permissions, --skip-permissions
  --allowedTools TOOLS        canonical snake_case names or aliases; status JSON exposes allowed_tools.available/aliases
  --resume [SESSION.jsonl|session-id|latest]
  --version, -V

Top-level commands:
  prompt <text>
  help
  version
  status
  sandbox
  acp [serve]
  dump-manifests
  bootstrap-plan
  agents
  mcp
  skills
  system-prompt
  init

claw acp is a local discoverability surface for editor-first users: it reports the current ACP/Zed status without starting the runtime. As of April 16, 2026, claw-code does not ship an ACP/Zed daemon or JSON-RPC entrypoint yet, and claw acp serve is only a status alias until the real protocol surface lands. Status queries exit 0 and expose the same machine-readable contract via --output-format json; malformed ACP invocations exit 1 with kind: unsupported_acp_invocation. --output-format accepts text or json in any casing. CLAW_OUTPUT_FORMAT=json selects JSON as the default for non-interactive commands, explicit flags override it, repeated flags warn on stderr, and status JSON exposes format_source, format_raw, and format_overridden. Help and doctor output also surface CLAW_LOG / RUST_LOG as the logging environment knobs. claw version --output-format json is the provenance probe for automation: it reports full git_sha, derived git_sha_short, is_dirty, branch, commit_date, commit_timestamp, rustc_version, runtime executable_path, and binary_provenance; the text report is available as human_readable instead of a duplicate message field. status --output-format json reports loaded project memory files under workspace.memory_files[] with each file's path, source (claude_md, claw_md, agents_md, or scoped/rule sources), origin, scope_path, outside_project, chars, and contributes; claw doctor --output-format json includes a dedicated memory check. Root instruction-file priority is CLAUDE.md, then CLAW.md, then AGENTS.md, discovery is bounded to the current git root when present (otherwise cwd only), and all non-duplicate loaded files contribute to the rendered system prompt. claw mcp --output-format json reports partial MCP config success: valid servers remain in servers[] while malformed siblings appear in invalid_servers[], with total_configured, valid_count, and invalid_count split out for automation. status mirrors this as mcp_validation, and doctor includes an mcp validation check. status --output-format json also reports partial hook config success under hook_validation: valid hook entries are retained while malformed or unknown-event siblings appear in invalid_hooks[], with valid_count, invalid_count, and typed kind fields (invalid_hooks_config or unknown_hook_event) for automation. doctor --output-format json includes a hook validation check, and config --output-format json includes hook_validation metadata with degraded status when invalid entries exist. Shorthand prompt mode honors the POSIX -- end-of-flags separator, so claw -- "-prompt-with-dash" and unknown dash-prefixed non-flag text stay on the prompt path instead of being treated as CLI options. claw dump-manifests is self-contained: it emits the Rust resolver inventory for the selected workspace (commands, tools, agents, skills, and bootstrap phases) without requiring an upstream Claude Code TypeScript checkout. Use --manifests-dir PATH only to scope resolver discovery to another directory.

The command surface is moving quickly. For the canonical live help text, run:

cargo run -p rusty-claude-cli -- --help

Slash Commands (REPL)

Tab completion expands slash commands, model aliases, permission modes, and recent session IDs.

The REPL now exposes a much broader surface than the original minimal shell:

• session / visibility: /help, /status, /sandbox, /cost, /resume, /session, /version, /usage, /stats
• workspace / git: /compact, /clear, /config, /memory, /init, /diff, /commit, /pr, /issue, /export, /hooks, /files, /release-notes
• discovery / debugging: /mcp, /agents, /skills, /doctor, /tasks, /context, /desktop
• automation / analysis: /review, /advisor, /insights, /security-review, /subagent, /team, /telemetry, /providers, /cron, and more
• plugin management: /plugin (with aliases /plugins, /marketplace)

Notable claw-first surfaces now available directly in slash form:

• /skills [list|show <name>|install <path>|uninstall <name>|help]
• /agents [list|show <name>|create <name>|help]
• /mcp [list|show <server>|help]
• /doctor
• /plugin [list|install <path>|enable <name>|disable <name>|uninstall <id>|update <id>]
• /subagent [list|steer <target> <msg>|kill <id>]

See ../USAGE.md for usage examples and run cargo run -p rusty-claude-cli -- --help for the live canonical command list.

Workspace Layout

rust/
├── Cargo.toml              # Workspace root
├── Cargo.lock
└── crates/
    ├── api/                # Provider clients + streaming + request preflight
    ├── commands/           # Shared slash-command registry + help rendering
    ├── compat-harness/     # Compatibility/parity harness utilities
    ├── mock-anthropic-service/ # Deterministic local Anthropic-compatible mock
    ├── plugins/            # Plugin metadata, manager, install/enable/disable surfaces
    ├── runtime/            # Session, config, permissions, MCP, prompts, auth/runtime loop
    ├── rusty-claude-cli/   # Main CLI binary (`claw`)
    ├── telemetry/          # Session tracing and usage telemetry types
    └── tools/              # Built-in tools, skill resolution, tool search, agent runtime surfaces

Crate Responsibilities

• api — provider clients, SSE streaming, request/response types, auth (ANTHROPIC_API_KEY + bearer-token support), request-size/context-window preflight
• commands — slash command definitions, parsing, help text generation, JSON/text command rendering
• compat-harness — compatibility and parity helpers for comparing behavior with upstream fixtures
• mock-anthropic-service — deterministic /v1/messages mock for CLI parity tests and local harness runs
• plugins — plugin metadata, install/enable/disable/update flows, plugin tool definitions, hook integration surfaces
• runtime — ConversationRuntime, config loading, session persistence, permission policy, MCP client lifecycle, system prompt assembly, usage tracking
• rusty-claude-cli — REPL, one-shot prompt, direct CLI subcommands, streaming display, tool call rendering, CLI argument parsing
• telemetry — session trace events and supporting telemetry payloads
• tools — tool specs + execution: Bash, ReadFile, WriteFile, EditFile, GlobSearch, GrepSearch, WebSearch, WebFetch, Agent, TodoWrite, NotebookEdit, Skill, ToolSearch, and runtime-facing tool discovery

Stats

• ~20K lines of Rust
• 9 crates in workspace
• Binary name: claw
• Default model: claude-opus-4-7
• Default permissions: workspace-write

License

See repository root.