Protocol contribution RFCs
This directory collects RFC-shaped documents that Burin Labs intends to
contribute to upstream agent-protocol working groups. Each RFC describes
a primitive that Harn already ships under a protocol's _meta
extensibility slot, so the upstream proposal can reference a running
reference implementation instead of starting from a design sketch.
Filing pattern
The Harn convention for cross-protocol primitives is:
- Ship the reference implementation first under the protocol's
designated extensibility slot (
_metafor ACP / MCP, the JSON-RPC envelope'smetadatafor A2A). This proves the shape end-to-end without disturbing upstream consumers. - Author an RFC document in this directory. Each RFC is written as a neutral standards-grade proposal: problem statement, wire-format schema, compatibility story, reference-impl status, and open questions for maintainers. The wire-format snippet matches the upstream repo's preferred dialect (TypeScript for ACP, JSON Schema for MCP, A2A JSON-RPC envelope for A2A).
- Open an upstream discussion when the RFC is ready. Treat the RFC doc as source material, then do a public-filing pass before posting: lead with neutral protocol semantics, deployed peer behavior, and public prior art rather than Harn or Burin-specific adoption claims. Keep the scope fixed inside the filed thread so maintainers can triage one proposal at a time.
- Track outcomes here. When a proposal lands upstream, update the
RFC's "Status" header and migrate the Harn
_metaenvelope to the standardized field locations in a follow-up PR. When a proposal is declined, record the decision in the RFC and keep the_metashape stable for downstream consumers.
Current RFCs
Statuses below were last verified on 2026-07-03. See the filing status ledger for the upstream PR, discussion, and issue states checked during triage.
Ambient reminder injection (#1829)
| RFC | Upstream | Status | Reference impl |
|---|---|---|---|
ACP session/inject_reminder | agentclientprotocol/agent-client-protocol | Discussion open (ACP #1224) | session/remind JSON-RPC method + _meta.harn.reminder-decorated transcript events |
A2A InjectTaskReminder | a2aproject/A2A | Discussion open (A2A #2027, filed 2026-07-03); revised to A2A v1.0 conventions 2026-07-03 | metadata.harn.reminder on outbound A2A task events |
MCP notifications/reminder | modelcontextprotocol/modelcontextprotocol | Discussion open (MCP #3007, filed 2026-07-03) | _meta.harn.reminder on MCP server-emitted notifications |
Suspend / resume + paused state (#1848)
| RFC | Upstream | Status | Reference impl |
|---|---|---|---|
ACP session/suspend | agentclientprotocol/agent-client-protocol | Discussion open (ACP #1233); no maintainer reply as of 2026-06-27 | __host_worker_suspend builtin + _meta.harn.suspend-decorated session updates; sibling to the already-shipped session/resume (ACP #1726) |
A2A TASK_STATE_PAUSED | a2aproject/A2A | Discussion open (A2A #1858); community feedback favors one PAUSED state plus structured pause metadata; no maintainer/TSC reply as of 2026-07-03; revised to A2A v1.0 conventions 2026-07-03 | metadata.harn.pause-decorated task status events |
Agent identity & provenance (#3330)
| RFC | Upstream | Status | Reference impl |
|---|---|---|---|
| A2A actor-chain extension | a2aproject/A2A | Issue open (A2A #2028, filed 2026-07-03); anchored to A2A #1937 + A2A #153 | ActorChain carried under metadata.actor_chain in the harn-serve A2A adapter |
MCP authenticatedIdentity | modelcontextprotocol/modelcontextprotocol | Pre-SEP discussion open (MCP #3008, filed 2026-07-03); SEP progression is sponsor-gated | Host-side "connected as" registry tracked under harn#3331 |
| MCP/OAuth actor-token positioning | oauth-wg / modelcontextprotocol/ext-auth | Feedback posted on oauth-wg #73 (2026-07-03) | ActorChain (RFC 8693 act shape) in harn-vm |
Scope
Authoring RFC documents in this repository is in scope for these PRs. Filing upstream discussions, issues, or PRs is the maintainer's explicit action - not a step any Harn contributor should take without the project owner asking for it. See #1829 for the upstream work that remains open.
Related
- Harn ACP/MCP extensions v1 - the
authoritative list of Harn-owned
_metafields that ride alongside upstream protocol payloads today. - System reminders - the language-level reminder primitive the reminder-injection RFCs are proposing to standardize.
- Transcript architecture - the underlying transcript event model that produces and consumes reminders.
suspend_agent/resume_agentbuiltins - the language-level cooperative suspend primitive the suspend/resume RFCs are proposing to standardize.- Filing status ledger - direct links and verification notes for the current upstream discussions, PRs, and issues.