- Agent side: --cap-manifest plus --cap-speak stream-json binding with transcript-diff frames, diff/transcript artifacts, session config - Orchestrator: PTY driver (settle heuristics on PtyProc/TuiVtScreen), stream-json, ACP-stdio (permission/elicit/fs/terminal serving) and A2A drivers (dual draft/current spelling, SSE mapping) - Sessions, fleets: worktrees, master plans, mediated routing, budget refusal, audit log, research auto-answerer, --cap CLI - cap.md contract with drift tests; research/cap-protocol archive - Suites 1119 + 16 green
2.1 KiB
2.1 KiB
ACP initialization (initialize, session/new baseline)
Metadata
| Field | Value |
|---|---|
| Institute | Molodetz Institute — Research & Retrieval Division |
| Subject | cap-protocol |
| Document type | Source Dossier |
| Tier | 1 |
| Source title | ACP Initialization |
| Source URL | https://agentclientprotocol.com/protocol/v1/initialization.md |
| Source type | specification |
| Source date (published) | Unknown, not stated (living docs) |
| Date researched | 2026-10-18 |
| Researched by | tai (agent), model: Muse Spark, on behalf of retoor |
| Research method | direct page fetch, read in full (initialization handshake, version negotiation, client capabilities) plus session-setup page for session/new |
| Confidence | High |
| Status | Active |
Summary
Connection baseline: initialize handshake negotiates client/agent capabilities (prompt content types, fs methods, terminals, elicitation modes, notices, compaction), and all agents MUST support session/new, session/prompt, session/cancel, session/update.
Key findings
- The four-method MUST baseline is the liveness contract tai's ACP driver can rely on for any agent.
- Capability negotiation is where tai declines surface (notices, compaction, URL elicitation) and advertises coding-profile grants (fs, terminals); initialize carries
protocolVersion: 1,clientCapabilities, andclientInfo. - Version negotiation: agent answers with the same version or its latest; tai speaks v1 only and closes on anything else.
session/newtakes{cwd, mcpServers}and returns{sessionId}(see the session-setup dossier).
Pros / strengths
- Explicit baseline + negotiation keeps a minimal driver compliant by construction.
Cons / limitations / caveats
- v1 only; v2 migration (method renames) deferred until an agent requires it.
- Auth methods and MCP server passing are out of scope for tai's driver.
Relevance to tai
Handshake design for the ACP driver: capability set tai advertises and the baseline it requires.
Changelog
| Date | Change |
|---|---|
| 2026-10-18 | Initial dossier created. |