{"$schema":"https://wellknown.network/schemas/agent-record-v1.json","schemaVersion":"1","id":"ag_sqgqmsvby5g2","handle":"tc39-mcp","url":"https://wellknown.network/agents/tc39-mcp","links":{"self":"https://wellknown.network/agents/tc39-mcp/record.json","html":"https://wellknown.network/agents/tc39-mcp","markdown":"https://wellknown.network/agents/tc39-mcp/record.md","api":"https://wellknown.network/api/v1/agents/tc39-mcp","status":"https://wellknown.network/api/v1/agents/tc39-mcp/status","claim":"https://wellknown.network/agents/tc39-mcp/claim","claimApi":"https://wellknown.network/api/v1/claims","claimDescriptor":"https://wellknown.network/agents/tc39-mcp/claim.json","badge":"https://wellknown.network/agents/tc39-mcp/badge.svg","openapi":"https://wellknown.network/openapi.json","history":"https://wellknown.network/api/v1/agents/tc39-mcp/history","tools":"https://wellknown.network/api/v1/agents/tc39-mcp/tools"},"ard":{"identifier":"urn:air:mcp.xyzzylabs.ai:server:tc39-mcp","type":"application/mcp-server-card+json"},"kind":"mcp_server","declared":{"name":"tc39-mcp","summary":"Independent MCP server for the TC39 specs (ECMA-262 + ECMA-402): clauses, search, diffs, history.","description":"Independent MCP server for the TC39 specs (ECMA-262 + ECMA-402): clauses, search, diffs, history.","publisher":{"name":"xyzzylabs","url":null},"homepage":"https://mcp.xyzzylabs.ai/tc39","repository":"https://github.com/xyzzylabs/tc39-mcp","version":"0.6.4","license":"MIT","protocols":["mcp"],"tags":["ecmascript","ecma262","ecma402","tc39","intl","javascript-spec","specification","language-spec","mcp","model-context-protocol"],"pricing":null,"endpoints":[{"url":"https://mcp.xyzzylabs.ai/tc39/mcp","type":"mcp_streamable_http","auth":null,"probeable":true},{"url":"npm:tc39-mcp","type":"package_npm","auth":null,"probeable":false}],"skills":null,"tools":null,"extra":{"updatedAt":"2026-10-07T15:33:45.308105Z","npmKeywords":["ecmascript","ecma262","ecma402","tc39","intl","javascript-spec","specification","language-spec","mcp","model-context-protocol"],"publishedAt":"2026-10-07T15:33:45.308105Z","registryName":"io.github.xyzzylabs/tc39-mcp"},"attribution":{"kind":"mcp_registry","name":"mcp_registry","license":"npm","repoUrl":"mcp_registry","summary":"mcp_registry","version":"mcp_registry","description":"mcp_registry","homepageUrl":"mcp_registry","publisherName":"mcp_registry"}},"derived":{"capabilities":[{"slug":"documents.contracts","name":"Contracts & Legal","confidence":0.885,"provenance":"derived"},{"slug":"dev.docs-lookup","name":"Documentation Lookup","confidence":0.54,"provenance":"derived"},{"slug":"dev.terminal","name":"Terminal & Shell","confidence":0.525,"provenance":"derived"},{"slug":"content.writing","name":"Writing & Editing","confidence":0.51,"provenance":"derived"},{"slug":"dev.package-management","name":"Packages & Dependencies","confidence":0.51,"provenance":"derived"}],"categories":["content","dev","documents"],"language":"en"},"observed":{"status":"live","statusReason":"Responded 4h ago.","lastOkAt":"2026-10-10T07:23:56.406Z","lastProbedAt":"2026-10-10T07:23:56.406Z","statusComputedAt":"2026-10-10T07:25:50.664Z","reliability30d":{"probes":110,"successRate":1,"p50Ms":74,"basis":"service","measures":{"availability":"availability","latency":"response time","tools":"tool surface observed","summary":"Checks reached the service itself."},"checks":{"total":108,"ok":108,"authBoundaryOk":0,"serviceOk":108,"note":"Counted from the observation rows for the window, checks of the server only (HTTP, A2A card, MCP initialize). ok = authBoundaryOk + serviceOk. `probes` is the sum of daily rollups and includes registry checks, so it can differ from `total`."}},"latestObservations":[{"at":"2026-10-10T07:23:56.406Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":43,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-10T00:27:51.753Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":148,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-09T17:28:54.489Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":120,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-09T11:26:25.963Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":153,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-09T04:28:59.978Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":62,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-08T22:24:37.195Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":70,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-08T16:29:02.687Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":73,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.5","protocolVersion":"2024-11-05"}},{"at":"2026-10-08T10:24:21.985Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":91,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.4","protocolVersion":"2024-11-05"}},{"at":"2026-10-08T03:24:22.541Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":63,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.4","protocolVersion":"2024-11-05"}},{"at":"2026-10-07T20:30:47.505Z","kind":"mcp_initialize","ok":true,"httpStatus":200,"latencyMs":86,"error":null,"detail":{"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"toolCount":17,"toolsHash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","serverName":"tc39-mcp","capabilities":["tools","prompts"],"serverVersion":"0.6.4","protocolVersion":"2024-11-05"}}],"tools":[{"name":"spec.about","description":"Self-description of this MCP server: package name + version, per-snapshot pin metadata (sha, fetched_at, biblio_commit, clause_count) for every supported (spec,"},{"name":"clause.get","description":"Fetch a parsed TC39 clause as structured JSON. `spec` selects '262' (default) or '402'. `edition` defaults to 'latest'. `at: '<sha>'` pins to a historical main "},{"name":"clause.list","description":"List parsed spec clauses with optional filters (kind, section prefix, has_algorithm). `spec` selects '262' or '402'. `at: '<sha>'` queries a historical main sna"},{"name":"spec.search","description":"Search the parsed spec by clause id / aoid / title (+ step text with `search_steps`). Aoid-exact ranks first. `at: '<sha>'` searches a historical main snapshot."},{"name":"proposal.list","description":"List TC39 proposals from the static index (tc39/proposals). Filter by spec ('262'|'402'), stage ('0'|'1'|'2'|'2.7'|'3'|'finished'|'inactive'|'active'), champion"},{"name":"proposal.get","description":"Fetch one TC39 proposal by slug (exact) or name (case-insensitive)."},{"name":"spec.grammar","description":"Query grammar productions captured from the spec's `<emu-grammar>` blocks. `{ nonterminal }` returns every production for that non-terminal (exact match); `{ co"},{"name":"spec.tables","description":"List or fetch parsed `<emu-table>` content. `{ id }` returns exactly that table (full columns + rows); otherwise list table summaries, optionally narrowed by a "},{"name":"spec.sdo_index","description":"Index Syntax-Directed Operations by the grammar production they're defined on. `by: 'production'` (default) groups SDOs under each production; `by: 'sdo'` group"},{"name":"clause.outline","description":"Return the section tree (table of contents) for a parsed (spec, edition). `depth` caps how deep the tree descends (1 = top-level only); `under` limits the tree "},{"name":"spec.global_search","description":"Run spec.search across both ECMA-262 and ECMA-402 in one call and interleave hits by score. Each hit is tagged with the spec it came from. Use it when you don't"},{"name":"spec.snapshots","description":"List the live (spec, edition, sha, fetched_at) snapshots the hosted Worker is serving from R2. Filter by `spec` ('262'|'402') or `edition` (e.g. 'main', 'es2026"},{"name":"spec.symbol_resolve","description":"Resolve spec notation like `[[Prototype]]` (internal slot), `%Object.prototype%` (well-known intrinsic), or `~number~` (sigil enum): return clauses that mention"},{"name":"spec.well_known_intrinsics","description":"Enumerate the well-known intrinsics in a spec with their probable defining clauses. Driven from the canonical §6.1.7.4 WKI table when present (ECMA-262), else a"},{"name":"spec.diff","description":"Clause-level diff of one clause across two editions of a spec. Reports identical / modified / added / removed plus a field-level breakdown (title, signature, st"},{"name":"spec.crossrefs","description":"For a clause id, return its outgoing references (clauses it cites) and/or incoming references (clauses that cite it — the back-reference index the parse alone d"},{"name":"test262.search","description":"Search the tc39/test262 conformance suite from its indexed front-matter. `query` AND-matches whitespace tokens (case-insensitive) across each test's description"}],"package":{"name":"tc39-mcp","registry":"npm","observedAt":"2026-10-10T07:26:32.651Z","publishedAt":"2026-09-08T12:49:51.269Z","latestVersion":"0.6.3","weeklyDownloads":62},"toolSurface":{"id":"ts_d2p9gkg7nzpe","endpointId":"ep_djmppqepy457","hash":"3d5f3ee21b8a29c90fb8be5ccaff08aac385887f1c710b5c01527bccfe127e6f","toolCount":17,"serverName":"tc39-mcp","serverVersion":"0.6.3","protocolVersion":"2024-11-05","firstSeenAt":"2026-09-12T10:26:37.447Z","lastSeenAt":"2026-10-10T07:23:56.403Z","observations":102,"toolNames":["spec.about","clause.get","clause.list","spec.search","proposal.list","proposal.get","spec.grammar","spec.tables","spec.sdo_index","clause.outline","spec.global_search","spec.snapshots","spec.symbol_resolve","spec.well_known_intrinsics","spec.diff","spec.crossrefs","test262.search"],"distinctSurfaces":1},"endpointFacts":[{"id":"ep_djmppqepy457","url":"https://mcp.xyzzylabs.ai/tc39/mcp","type":"mcp_streamable_http","factsCheckedAt":"2026-10-05T16:26:24.052Z","auth":{"observedAt":"2026-10-05T16:26:24.064Z","authRequired":false,"scheme":null,"resourceMetadata":null,"authorizationServer":null,"conformance":{"dpop":false,"rfc8414":false,"rfc9728":false,"pkceS256":false,"clientIdMetadataDocument":false,"dynamicClientRegistration":false}},"tls":{"observedAt":"2026-10-05T16:26:24.082Z","protocol":"TLSv1.3","chainValid":true,"chainError":null,"hostMatches":true,"subject":"xyzzylabs.ai","issuer":{"commonName":"WE1","organization":"Google Trust Services"},"validFrom":"2026-08-23T08:50:29.000Z","validTo":"2026-11-21T09:50:26.000Z","daysToExpiry":41,"sanCount":3,"fingerprint256":"1C:9F:57:20:04:B8:CF:64:5B:F8:31:5F:94:29:9C:16:FD:1F:C2:7A:CE:09:93:73:A9:E4:11:62:40:CB:B6:CC"}}]},"verification":{"claimed":false,"claimedAt":null,"proofs":[]},"provenance":{"sources":[{"source":"npm","key":"tc39-mcp","url":"https://www.npmjs.com/package/tc39-mcp","firstSeenAt":"2026-09-06T01:17:37.829Z","fetchedAt":"2026-09-22T19:20:31.689Z","normalizedAt":"2026-09-22T19:20:31.689Z"},{"source":"mcp_registry","key":"io.github.xyzzylabs/tc39-mcp","url":"https://registry.modelcontextprotocol.io/v0/servers/io.github.xyzzylabs%2Ftc39-mcp","firstSeenAt":"2026-09-07T06:18:12.800Z","fetchedAt":"2026-10-08T16:20:53.202Z","normalizedAt":"2026-10-08T16:20:53.202Z"}]},"firstSeenAt":"2026-09-06T01:17:37.829Z","updatedAt":"2026-10-10T07:26:32.651Z"}