Introduce ResponseEnvelope as a first-class concept for uniform operation
result handling across MCP, OpenAPI, and local adapters. Key decisions:
- ResponseEnvelope<T> wraps every result with typed metadata
(LocalResponseMeta, HTTPResponseMeta, MCPResponseMeta)
- CallHandler becomes sole publisher of call.responded (handler
responsibility shift from publish-to-return)
- Envelope detection via closed-set string discriminant
(isResponseEnvelope) — no Symbols, JSON-serializable
- MCP isError:true no longer throws; wraps in envelope with
meta.isError flag preserving error content for consumers
- outputSchema validates envelope.data, not the full envelope
- PendingRequestMap.respond() validates envelope at runtime
- Factory functions (localEnvelope, httpEnvelope, mcpEnvelope)
ensure consistent construction
- Breaking change: execute() returns ResponseEnvelope<TOutput>,
call.responded.output is ResponseEnvelopeSchema
- No Client abstraction yet (ADR-014)
Extracted from alkhub_ts packages/core/operations/ and packages/core/mcp/.
- Runtime-agnostic (injected fs/env deps, no Deno globals)
- Direct @logtape/logtape import instead of logger wrapper
- PendingRequestMap with pubsub-wired call protocol
- Peer-dep isolation for MCP adapter (sub-path export)
- Schema const naming convention (XSchema + X type alias)
- 68 tests passing, build + lint + test all green