crush system prompt

--- name: crush-config description: Use when the user needs help configuring Crush — working with crush.json, setting up providers, configuring LSPs, adding MCP servers, managing skills or permissions, or changing Crush behavior. --- # Crush Configuration Crush uses JSON configuration files with the following priority (highest to lowest): 1. `.crush.json` (project-local, hidden) 2. `crush.json` (project-local) 3. `$XDG_CONFIG_HOME/crush/crush.json` or `$HOME/.config/crush/crush.json` (global) ## Basic Structure ```json { "$schema": "https://charm.land/crush.json", "models": {}, "providers": {}, "mcp": {}, "lsp": {}, "hooks": {}, "options": {}, "permissions": {}, "tools": {} } ``` The `$schema` property enables IDE autocomplete but is optional. ## Shell Expansion Crush runs selected string fields through an embedded bash-compatible shell at load time, so values can pull from env vars, files, or helper commands. Supported constructs (match the `bash` tool): - `$VAR` and `${VAR}` - `${VAR:-default}`, `${VAR:+alt}`, `${VAR:?message}` - `$(command)` with full quoting and nesting - Single- and double-quoted strings, escapes Default semantics match bash: an unset variable expands to an empty string, no error. A failing `$(command)` is always a hard error. For required credentials, use `${VAR:?message}` so a missing variable fails loudly at load time with your message. ```json { "api_key": "${CODEBERG_TOKEN:?set CODEBERG_TOKEN}" } ``` ### Which fields expand | Surface | Expansion | | --------------------------------------------------- | --------- | | Provider `api_key`, `base_url`, `api_endpoint` | yes | | Provider `extra_headers` | yes | | Provider `extra_body` | **no** | | MCP `command`, `args`, `env`, `headers`, `url` | yes | | LSP `command`, `args`, `env` | yes | | Hook `command` | runs via `sh -c`, not the resolver | `extra_body` is a JSON passthrough. If you need env-driven values in a request body, put them in `extra_headers`, `api_key`, or `base_url` instead. ### Empty-resolved headers are dropped When a header value resolves to the empty string (unset variable, `$(echo)`, or literal `""`), the header is omitted from the outgoing request. This keeps optional env-gated headers like `"OpenAI-Organization": "$OPENAI_ORG_ID"` working cleanly when the var isn't set. Applies to MCP `headers` and provider `extra_headers`. ### Security note `crush.json` is trusted code. Any `$(...)` in it runs at load time with the invoking user's shell privileges, before the UI appears. Don't launch Crush in a directory whose `crush.json` you haven't reviewed. ## Common Tasks - Add a custom provider: add an entry under `providers` with `type`, `base_url`, `api_key`, and `models`. - Disable a builtin or local skill: add the skill name to `options.disabled_skills`. - Add an MCP server: add an entry under `mcp` with `type` and either `command` (stdio) or `url` (http/sse). ## Model Selection ```json { "models": { "large": { "model": "claude-sonnet-4-20250514", "provider": "anthropic", "max_tokens": 16384 }, "small": { "model": "claude-haiku-4-20250514", "provider": "anthropic" } } } ``` - `large` is the primary coding model; `small` is for summarization. - Only `model` and `provider` are required. - Optional tuning: `reasoning_effort`, `think`, `max_tokens`, `temperature`, `top_p`, `top_k`, `frequency_penalty`, `presence_penalty`, `provider_options`. ## Custom Providers ```json { "providers": { "deepseek": { "type": "openai-compat", "base_url": "https://api.deepseek.com/v1", "api_key": "$DEEPSEEK_API_KEY", "models": [ { "id": "deepseek-chat", "name": "Deepseek V3", "context_window": 64000 } ] } } } ``` - `type` (required): `openai`, `openai-compat`, or `anthropic` - `api_key`, `base_url`, `api_endpoint`, and `extra_headers` are shell-expanded (see [Shell Expansion](#shell-expansion)). - `extra_body` is a JSON passthrough and is **not** expanded. - Additional fields: `disable`, `system_prompt_prefix`, `extra_headers`, `extra_body`, `provider_options`. ## LSP Configuration ```json { "lsp": { "go": { "command": "gopls", "env": { "GOPATH": "$HOME/go" } }, "typescript": { "command": "typescript-language-server", "args": ["--stdio"] } } } ``` - `command` (required), `args`, `env` cover most setups. - `command`, `args`, and `env` values are shell-expanded (see [Shell Expansion](#shell-expansion)). - Additional fields: `disabled`, `filetypes`, `root_markers`, `init_options`, `options`, `timeout`. ## MCP Servers ```json { "mcp": { "filesystem": { "type": "stdio", "command": "node", "args": ["/path/to/mcp-server.js"] }, "github": { "type": "http", "url": "https://api.githubcopilot.com/mcp/", "headers": { "Authorization": "Bearer $GH_PAT" } } } } ``` - `type` (required): `stdio`, `sse`, or `http` - `command`, `args`, `env`, `headers`, and `url` are shell-expanded (see [Shell Expansion](#shell-expansion)). - Additional fields: `env`, `disabled`, `disabled_tools`, `timeout`. ## Options ```json { "options": { "skills_paths": ["./skills"], "disabled_tools": ["bash", "sourcegraph"], "disabled_skills": ["crush-config"], "tui": { "compact_mode": false, "diff_mode": "unified", "transparent": false }, "auto_lsp": true, "debug": false, "debug_lsp": false, "attribution": { "trailer_style": "assisted-by", "generated_with": true } } } ``` > [!IMPORTANT] > The following skill paths are loaded by default and DO NOT NEED to be added to `skills_paths`: > `.agents/skills`, `.crush/skills`, `.claude/skills`, `.cursor/skills` Other options: `context_paths`, `progress`, `disable_notifications`, `disable_auto_summarize`, `disable_metrics`, `disable_provider_auto_update`, `disable_default_providers`, `data_directory`, `initialize_as`. ## User-Invocable Skills Skills can be made invocable as commands from the commands palette. Add `user-invocable: true` to the skill's YAML frontmatter: ```yaml --- name: my-skill description: A skill that can be invoked as a command. user-invocable: true --- ``` User-invocable skills appear in the commands palette with a prefix: - Skills from global directories: `user:skill-name` - Skills from project directories: `project:skill-name` When invoked, the skill's instructions are loaded into the conversation context. To prevent the model from auto-triggering a skill (while still allowing user invocation), add `disable-model-invocation: true`: ```yaml --- name: my-skill description: Only invocable by users, not the model. user-invocable: true disable-model-invocation: true --- ``` Skills with `disable-model-invocation` won't appear in the model's available skills list but can still be invoked manually by users. ## Hooks Hooks are user-defined shell commands that fire on agent events. Currently only `PreToolUse` is supported, which runs before a tool is executed. ```json { "hooks": { "PreToolUse": [ { "matcher": "^(edit|write|multiedit)$", "command": ".crush/hooks/protect-files.sh" }, { "matcher": "^bash$", "command": ".crush/hooks/no-haskell.sh" } ] } } ``` ### Hook Properties - `command` (required): Shell command to execute. Runs via `sh -c`. - `matcher` (optional): Regex pattern tested against the tool name. Empty or absent means match all tools. - `timeout` (optional): Timeout in seconds. Defaults to 30. ### Event Name Normalization Event names are case-insensitive and accept snake_case variants: `PreToolUse`, `pretooluse`, `pre_tool_use`, and `PRE_TOOL_USE` all work. ### How Hooks Work 1. When a tool is about to be called, all `PreToolUse` hooks with a matching `matcher` (or no matcher) run in parallel. 2. Duplicate commands are deduplicated — each unique command runs at most once. 3. The hook receives JSON on **stdin** and hook-specific **environment variables**. ### Hook Input (stdin) A JSON payload is piped to the hook command: ```json { "event": "PreToolUse", "session_id": "abc-123", "cwd": "/path/to/project", "tool_name": "bash", "tool_input": {"command": "ls -la"} } ``` ### Hook Environment Variables | Variable | Description | |---|---| | `CRUSH_EVENT` | Event name (e.g. `PreToolUse`) | | `CRUSH_TOOL_NAME` | Name of the tool being called | | `CRUSH_SESSION_ID` | Current session ID | | `CRUSH_CWD` | Current working directory | | `CRUSH_PROJECT_DIR` | Project root directory | | `CRUSH_TOOL_INPUT_COMMAND` | Value of `command` from tool input (if present) | | `CRUSH_TOOL_INPUT_FILE_PATH` | Value of `file_path` from tool input (if present) | ### Hook Output **Exit code 0** — the hook succeeded. Stdout is parsed as JSON: ```json {"decision": "allow", "context": "optional context appended to tool result"} ``` - `decision`: `allow` to explicitly allow, `deny` to block, `none` (or omit) for no opinion. - `reason`: Explanation text (used when denying). - `context`: Extra context appended to the tool result. - `updated_input`: Replacement JSON for the tool input. Last non-empty value wins. **Exit code 2** — the tool call is blocked. Stderr is used as the deny reason. ```bash echo "No Haskell allowed" >&2 exit 2 ``` **Any other exit code** — non-blocking error. The tool call proceeds as normal. ### Claude Code Compatibility Crush also supports the Claude Code hook output format: ```json { "hookSpecificOutput": { "permissionDecision": "allow", "permissionDecisionReason": "Auto-approved", "updatedInput": {"command": "echo rewritten"} } } ``` Existing Claude Code hooks should work without modification. ### Decision Aggregation When multiple hooks match, their decisions are aggregated: - **Deny wins over allow** — if any hook denies, the tool call is blocked. - **Allow wins over none** — if no hook denies but at least one allows, the call proceeds. - All deny reasons are concatenated (newline-separated). - All context strings are concatenated (newline-separated). - For `updated_input`, the last non-empty value wins. ## Tool Permissions ```json { "permissions": { "allowed_tools": ["view", "ls", "grep", "edit"] } } ``` ## Environment Variables - `CRUSH_GLOBAL_CONFIG` - Override global config location - `CRUSH_GLOBAL_DATA` - Override data directory location - `CRUSH_SKILLS_DIR` - Override default skills directory