> ## Documentation Index > Fetch the complete documentation index at: https://docs.fluffbuzz.com/llms.txt > Use this file to discover all available pages before exploring further. # ACP Run the [Agent Client Protocol (ACP)](https://agentclientprotocol.com/) bridge that talks to an FluffBuzz Gateway. This command speaks ACP over stdio for IDEs and forwards prompts to the Gateway over WebSocket. It keeps ACP sessions mapped to Gateway session keys. `fluffbuzz acp` is a Gateway-backed ACP bridge, not a full ACP-native editor runtime. It focuses on session routing, prompt delivery, and basic streaming updates. If you want an external MCP client to talk directly to FluffBuzz channel conversations instead of hosting an ACP harness session, use [`fluffbuzz mcp serve`](/cli/mcp) instead. ## What this is not This page is often confused with ACP harness sessions. `fluffbuzz acp` means: * FluffBuzz acts as an ACP server * an IDE or ACP client connects to FluffBuzz * FluffBuzz forwards that work into a Gateway session This is different from [ACP Agents](/tools/acp-agents), where FluffBuzz runs an external harness such as Codex or Claude Code through `acpx`. Quick rule: * editor/client wants to talk ACP to FluffBuzz: use `fluffbuzz acp` * FluffBuzz should launch Codex/Claude/Gemini as an ACP harness: use `/acp spawn` and [ACP Agents](/tools/acp-agents) ## Compatibility Matrix | ACP area | Status | Notes | | --------------------------------------------------------------------- | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `initialize`, `newSession`, `prompt`, `cancel` | Implemented | Core bridge flow over stdio to Gateway chat/send + abort. | | `listSessions`, slash commands | Implemented | Session list works against Gateway session state; commands are advertised via `available_commands_update`. | | `loadSession` | Partial | Rebinds the ACP session to a Gateway session key and replays stored user/assistant text history. Tool/system history is not reconstructed yet. | | Prompt content (`text`, embedded `resource`, images) | Partial | Text/resources are flattened into chat input; images become Gateway attachments. | | Session modes | Partial | `session/set_mode` is supported and the bridge exposes initial Gateway-backed session controls for thought level, tool verbosity, reasoning, usage detail, and elevated actions. Broader ACP-native mode/config surfaces are still out of scope. | | Session info and usage updates | Partial | The bridge emits `session_info_update` and best-effort `usage_update` notifications from cached Gateway session snapshots. Usage is approximate and only sent when Gateway token totals are marked fresh. | | Tool streaming | Partial | `tool_call` / `tool_call_update` events include raw I/O, text content, and best-effort file locations when Gateway tool args/results expose them. Embedded terminals and richer diff-native output are still not exposed. | | Per-session MCP servers (`mcpServers`) | Unsupported | Bridge mode rejects per-session MCP server requests. Configure MCP on the FluffBuzz gateway or agent instead. | | Client filesystem methods (`fs/read_text_file`, `fs/write_text_file`) | Unsupported | The bridge does not call ACP client filesystem methods. | | Client terminal methods (`terminal/*`) | Unsupported | The bridge does not create ACP client terminals or stream terminal ids through tool calls. | | Session plans / thought streaming | Unsupported | The bridge currently emits output text and tool status, not ACP plan or thought updates. | ## Known Limitations * `loadSession` replays stored user and assistant text history, but it does not reconstruct historic tool calls, system notices, or richer ACP-native event types. * If multiple ACP clients share the same Gateway session key, event and cancel routing are best-effort rather than strictly isolated per client. Prefer the default isolated `acp:` sessions when you need clean editor-local turns. * Gateway stop states are translated into ACP stop reasons, but that mapping is less expressive than a fully ACP-native runtime. * Initial session controls currently surface a focused subset of Gateway knobs: thought level, tool verbosity, reasoning, usage detail, and elevated actions. Model selection and exec-host controls are not yet exposed as ACP config options. * `session_info_update` and `usage_update` are derived from Gateway session snapshots, not live ACP-native runtime accounting. Usage is approximate, carries no cost data, and is only emitted when the Gateway marks total token data as fresh. * Tool follow-along data is best-effort. The bridge can surface file paths that appear in known tool args/results, but it does not yet emit ACP terminals or structured file diffs. ## Usage ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} fluffbuzz acp # Remote Gateway fluffbuzz acp --url wss://gateway-host:18789 --token # Remote Gateway (token from file) fluffbuzz acp --url wss://gateway-host:18789 --token-file ~/.fluffbuzz/gateway.token # Attach to an existing session key fluffbuzz acp --session agent:main:main # Attach by label (must already exist) fluffbuzz acp --session-label "support inbox" # Reset the session key before the first prompt fluffbuzz acp --session agent:main:main --reset-session ``` ## ACP client (debug) Use the built-in ACP client to sanity-check the bridge without an IDE. It spawns the ACP bridge and lets you type prompts interactively. ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} fluffbuzz acp client # Point the spawned bridge at a remote Gateway fluffbuzz acp client --server-args --url wss://gateway-host:18789 --token-file ~/.fluffbuzz/gateway.token # Override the server command (default: fluffbuzz) fluffbuzz acp client --server "node" --server-args fluffbuzz.mjs acp --url ws://127.0.0.1:19001 ``` Permission model (client debug mode): * Auto-approval is allowlist-based and only applies to trusted core tool IDs. * `read` auto-approval is scoped to the current working directory (`--cwd` when set). * ACP only auto-approves narrow readonly classes: scoped `read` calls under the active cwd plus readonly search tools (`search`, `web_search`, `memory_search`). Unknown/non-core tools, out-of-scope reads, exec-capable tools, control-plane tools, mutating tools, and interactive flows always require explicit prompt approval. * Server-provided `toolCall.kind` is treated as untrusted metadata (not an authorization source). * This ACP bridge policy is separate from ACPX harness permissions. If you run FluffBuzz through the `acpx` backend, `plugins.entries.acpx.config.permissionMode=approve-all` is the break-glass “yolo” switch for that harness session. ## How to use this Use ACP when an IDE (or other client) speaks Agent Client Protocol and you want it to drive an FluffBuzz Gateway session. 1. Ensure the Gateway is running (local or remote). 2. Configure the Gateway target (config or flags). 3. Point your IDE to run `fluffbuzz acp` over stdio. Example config (persisted): ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} fluffbuzz config set gateway.remote.url wss://gateway-host:18789 fluffbuzz config set gateway.remote.token ``` Example direct run (no config write): ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} fluffbuzz acp --url wss://gateway-host:18789 --token # preferred for local process safety fluffbuzz acp --url wss://gateway-host:18789 --token-file ~/.fluffbuzz/gateway.token ``` ## Selecting agents ACP does not pick agents directly. It routes by the Gateway session key. Use agent-scoped session keys to target a specific agent: ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} fluffbuzz acp --session agent:main:main fluffbuzz acp --session agent:design:main fluffbuzz acp --session agent:qa:bug-123 ``` Each ACP session maps to a single Gateway session key. One agent can have many sessions; ACP defaults to an isolated `acp:` session unless you override the key or label. Per-session `mcpServers` are not supported in bridge mode. If an ACP client sends them during `newSession` or `loadSession`, the bridge returns a clear error instead of silently ignoring them. If you want ACPX-backed sessions to see FluffBuzz plugin tools or selected built-in tools such as `cron`, enable the gateway-side ACPX MCP bridges instead of trying to pass per-session `mcpServers`. See [ACP Agents](/tools/acp-agents#plugin-tools-mcp-bridge) and [FluffBuzz tools MCP bridge](/tools/acp-agents#fluffbuzz-tools-mcp-bridge). ## Use from `acpx` (Codex, Claude, other ACP clients) If you want a coding agent such as Codex or Claude Code to talk to your FluffBuzz bot over ACP, use `acpx` with its built-in `fluffbuzz` target. Typical flow: 1. Run the Gateway and make sure the ACP bridge can reach it. 2. Point `acpx fluffbuzz` at `fluffbuzz acp`. 3. Target the FluffBuzz session key you want the coding agent to use. Examples: ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} # One-shot request into your default FluffBuzz ACP session acpx fluffbuzz exec "Summarize the active FluffBuzz session state." # Persistent named session for follow-up turns acpx fluffbuzz sessions ensure --name codex-bridge acpx fluffbuzz -s codex-bridge --cwd /path/to/repo \ "Ask my FluffBuzz work agent for recent context relevant to this repo." ``` If you want `acpx fluffbuzz` to target a specific Gateway and session key every time, override the `fluffbuzz` agent command in `~/.acpx/config.json`: ```json theme={"theme":{"light":"min-light","dark":"min-dark"}} { "agents": { "fluffbuzz": { "command": "env FLUFFBUZZ_HIDE_BANNER=1 FLUFFBUZZ_SUPPRESS_NOTES=1 fluffbuzz acp --url ws://127.0.0.1:18789 --token-file ~/.fluffbuzz/gateway.token --session agent:main:main" } } } ``` For a repo-local FluffBuzz checkout, use the direct CLI entrypoint instead of the dev runner so the ACP stream stays clean. For example: ```bash theme={"theme":{"light":"min-light","dark":"min-dark"}} env FLUFFBUZZ_HIDE_BANNER=1 FLUFFBUZZ_SUPPRESS_NOTES=1 node fluffbuzz.mjs acp ... ``` This is the easiest way to let Codex, Claude Code, or another ACP-aware client pull contextual information from an FluffBuzz agent without scraping a terminal. ## Zed editor setup Add a custom ACP agent in `~/.config/zed/settings.json` (or use Zed’s Settings UI): ```json theme={"theme":{"light":"min-light","dark":"min-dark"}} { "agent_servers": { "FluffBuzz ACP": { "type": "custom", "command": "fluffbuzz", "args": ["acp"], "env": {} } } } ``` To target a specific Gateway or agent: ```json theme={"theme":{"light":"min-light","dark":"min-dark"}} { "agent_servers": { "FluffBuzz ACP": { "type": "custom", "command": "fluffbuzz", "args": [ "acp", "--url", "wss://gateway-host:18789", "--token", "", "--session", "agent:design:main" ], "env": {} } } } ``` In Zed, open the Agent panel and select “FluffBuzz ACP” to start a thread. ## Session mapping By default, ACP sessions get an isolated Gateway session key with an `acp:` prefix. To reuse a known session, pass a session key or label: * `--session `: use a specific Gateway session key. * `--session-label