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MCP server

MCP glossary

The terms this surface uses, defined once.

Contract (presentation contract) — the versioned shape of every projection payload; v4 in this release, carried as contract_version on every response. Data class — one of the two closed scope units (stream-state, cost-data) a token does or does not carry. Denial shape — the single byte-identical error body every denial returns; the cause lives only in the record, keyed by ref. Front door — the OAuth surface: discovery metadata, /authorize, /token, and the bearer middleware. Horizon — which streams a fleet read includes: live (default; open work) or all. Projection — a rendering of the record; this server is the record's third projection, after the CLI and the exported artifacts. Never the source. Self-issued AS — the server's built-in OAuth 2.1 authorization server: PKCE-only, RS256, 15-minute tokens, no refresh grant. Trust list (ISSUERS.md) — the human-gated document naming which external issuers may authenticate callers, with pinned audience and algorithm per issuer. Tenant slice — the row-level narrowing of the projection to a tenant token's named streams. Tool budget — the stacked response-size discipline: live horizon, honest summary, limit

  • cursor, tabular formats, and the 200,000-byte cap-as-error. Virtual path — the access-log resolution of one POST /mcp wire request into the method/tool actually invoked (POST /mcp/tools/<name>).