@mimicai/adapter-slack

Slack Web API mock adapter for Mimic. 27 curated methods covering channels, messages, threads, users, reactions, pins, files, and search — all backed by an in-memory state store.

Targeted at AI agents that need to read internal communication context (e.g. the Briefing Agent's #deals mentions, channel sentiment, thread state) during testing without touching a real workspace.

Install

npm install @mimicai/adapter-slack

What it covers

| Surface | Methods | |---------|---------| | Auth & team | auth.test, team.info | | Users | users.list, users.info, users.lookupByEmail, users.profile.get | | Conversations | conversations.list, conversations.history, conversations.replies, conversations.info, conversations.members, conversations.create, conversations.open | | Chat | chat.postMessage, chat.postEphemeral, chat.update, chat.delete | | Reactions | reactions.add, reactions.remove, reactions.get, reactions.list | | Pins | pins.list, pins.add, pins.remove | | Files | files.list, files.info | | Search | search.messages |

The Slack admin/enterprise surface (admin., apps., workflows., calls., sockets, OAuth flow, view modals) is intentionally out of scope. Methods Slack documents but doesn't include in its OpenAPI spec — bookmarks and search.files — are noted in the codegen as known gaps.

Slack idioms the adapter implements

• { ok: true|false } envelope — every response is wrapped via a Fastify preSerialization hook. Handlers return the inner payload; the wrapper adds ok and an error code on failure.
• Cursor pagination — next_cursor in response_metadata, opaque c_<id> token, empty string sentinel for last page.
• Form-encoded bodies — @fastify/formbody is registered conditionally (test helpers already register it).
• Thread semantics — top-level message ts equals its thread_ts when it has replies; conversations.replies returns parent + chronological replies; conversations.history returns only top-level messages.
• Bot identity bootstrap — seedDefaultFixtures creates a default workspace + bot user so auth.test succeeds without persona data.

Auth

Real Slack uses OAuth bot tokens (xoxb-…) and user tokens (xoxp-…). For mock usage, Bearer xoxb-<personaId>-… (or xoxp-) resolves to that persona id.

MCP tools (10)

get_slack_team_info, lookup_slack_user_by_email, list_slack_users, list_slack_channels, get_slack_conversation_history, get_slack_thread_replies, search_slack_messages, post_slack_message, add_slack_reaction, list_slack_pins.

lookup_slack_user_by_email is the high-value tool for the Briefing Agent — given a meeting attendee's email, find the matching workspace user.

Running

Standalone MCP server (stdio):

npx -y @mimicai/adapter-slack mcp

Or via mimic host:

{
  "apis": {
    "slack": { "enabled": true, "mcp": true }
  }
}

Regenerating from spec

curl -fsSL https://raw.githubusercontent.com/slackapi/slack-api-specs/master/web-api/slack_web_openapi_v2.json \
  -o packages/adapters/adapter-slack/slack-spec.json
pnpm --filter @mimicai/adapter-slack generate

The codegen (scripts/slack-codegen.ts) walks Slack's Swagger 2.0 spec, filters by an INCLUDE_PATHS whitelist, and emits routes/resource-specs/schemas with hand-tuned factory bodies preserved across regeneration.

License

Apache 2.0