modelcontextprotocol

modelcontextprotocol/typescript-sdk

The official TypeScript SDK for Model Context Protocol servers and clients

Stars: 13.4k
Forks: 2.2k
Open beginner issues: 25
Indexed issues: 300
Avg merge: 3d 15h
Merged PRs (30d): 4

Dominant language: TypeScript
License: No license data
Last GitHub push: Sep 16, 2026
Latest indexed: Sep 20, 2026
Contributing guide: Contributing guide
Code of conduct: Code of conduct
Beginner labels: good first issue help wanted

Beginner friendly Everything

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300 open issues indexed

Error: Browser navigation is locked during ChatGPT login Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

modelcontextprotocol/typescript-sdk#2834 · Opened Sep 19, 2026
PKCE verification: 2025-11-25 requires refusing when `code_challenge_methods_supported` is absent, which conflicts with the #832 / #992 resolution Open

Difficulty 5/5 Over a week Newbie friendliness 28/100

modelcontextprotocol/typescript-sdk#2831 · Opened Sep 18, 2026
[v2] Server-side hook for subscriptions/listen resource subscriptions (attach/detach per URI) Open

Difficulty 5/5 Over a week Newbie friendliness 38/100

modelcontextprotocol/typescript-sdk#2827 · 1 comment · Opened Sep 17, 2026
[v2] _resetTimeout never updates startTime, so totalElapsed keeps accumulating from the original Open

v2

Difficulty 3/5 1-2 days Newbie friendliness 72/100

modelcontextprotocol/typescript-sdk#2816 · Opened Sep 14, 2026
License metadata clarification for server/core 2.0.0 Open

Difficulty 4/5 3-5 days Newbie friendliness 52/100

modelcontextprotocol/typescript-sdk#2801 · Opened Sep 13, 2026
TS SDK Add first-class SEP-2640 Skills extension APIs Open

Difficulty 5/5 Over a week Newbie friendliness 35/100

modelcontextprotocol/typescript-sdk#2798 · Opened Sep 12, 2026
skills/list, skills/get, resources/directory/read always fail: codec strips resultType before re-validating it Open

Difficulty 3/5 1-2 days Newbie friendliness 76/100

modelcontextprotocol/typescript-sdk#2789 · 1 comment · Opened Sep 11, 2026
A handler that throws McpError produces a double-prefixed message on the client Open

Difficulty 3/5 1-2 days Newbie friendliness 68/100

modelcontextprotocol/typescript-sdk#2786 · 3 comments · Opened Sep 10, 2026
Auth metadata discovery: fallback URL built on resource host instead of authorization-server host Open

Difficulty 2/5 1-3 hours Newbie friendliness 74/100

modelcontextprotocol/typescript-sdk#2784 · Opened Sep 10, 2026
Auth metadata discovery: fallback only triggers on 404, misses 401/403 Open

Difficulty 2/5 1-3 hours Newbie friendliness 82/100

modelcontextprotocol/typescript-sdk#2783 · 1 comment · Opened Sep 10, 2026
OAuth client_secret comparison in clientAuth.ts is not constant-time Open

Difficulty 2/5 1-3 hours Newbie friendliness 35/100

modelcontextprotocol/typescript-sdk#2780 · Opened Sep 10, 2026
Where does validation of a peer's declarations belong? Four things the client accepts today Open

Difficulty 5/5 Over a week Newbie friendliness 30/100

modelcontextprotocol/typescript-sdk#2777 · 1 comment · 1 reaction · Opened Sep 9, 2026
stderr: 'pipe' deadlocks the session if the consumer never reads transport.stderr Open

Difficulty 3/5 1-2 days Newbie friendliness 72/100

modelcontextprotocol/typescript-sdk#2776 · 3 comments · Opened Sep 9, 2026
Transport errors are reported only on onerror; awaiting callers always get "MCP error -32000: Connection closed" Open

Difficulty 4/5 3-5 days Newbie friendliness 52/100

modelcontextprotocol/typescript-sdk#2775 · 3 comments · Opened Sep 9, 2026
authorizationHandler drops the OAuth state parameter on error redirects Open

Difficulty 2/5 1-3 hours Newbie friendliness 88/100

modelcontextprotocol/typescript-sdk#2773 · Opened Sep 9, 2026
[v2] Streamable HTTP client does not clear stale resumption token after an empty SSE id Open

Difficulty 3/5 1-2 days Newbie friendliness 76/100

modelcontextprotocol/typescript-sdk#2769 · 3 comments · Opened Sep 8, 2026
Doc comments misattribute the token-endpoint TLS check to SEP-2207 (which is OIDC refresh / `offline_access`) Open

Difficulty 1/5 Under an hour Newbie friendliness 92/100

modelcontextprotocol/typescript-sdk#2766 · 1 comment · Opened Sep 7, 2026
[v2] Typescript: optional content when structuredContent is present Open

v2

Difficulty 3/5 1-2 days Newbie friendliness 62/100

modelcontextprotocol/typescript-sdk#2755 · Opened Sep 3, 2026
[v2] Should raise error at build time if zod outputSchema is not consistent with the structuredContent type Open

v2

Difficulty 4/5 3-5 days Newbie friendliness 50/100

modelcontextprotocol/typescript-sdk#2754 · 2 comments · Opened Sep 3, 2026
Server auth defaults silently produce RFC 9728-noncompliant discovery when the MCP endpoint has a path Open

Difficulty 2/5 1-2 days Newbie friendliness 72/100

modelcontextprotocol/typescript-sdk#2751 · Opened Sep 3, 2026
v1.x and v2 disagree on validating an error result's structuredContent — and the v1.x comment describes the v2 behaviour Open

Difficulty 4/5 3-5 days Newbie friendliness 48/100

modelcontextprotocol/typescript-sdk#2748 · 3 comments · Opened Sep 2, 2026
experimental.tasks.getTaskResult() throws TypeError: Cannot read properties of undefined (reading '_zod') when the optional result schema is omitted Open

Difficulty 2/5 1-3 hours Newbie friendliness 84/100

modelcontextprotocol/typescript-sdk#2742 · 2 comments · Opened Aug 31, 2026
StreamableHTTPClientTransport leaves POST requests pending when their SSE response ends or errors Open

Difficulty 4/5 3-5 days Newbie friendliness 52/100

modelcontextprotocol/typescript-sdk#2739 · 5 comments · Opened Aug 30, 2026
Client.listTools() silently drops pages when a server repeats a cursor Open

Difficulty 3/5 1-2 days Newbie friendliness 74/100

modelcontextprotocol/typescript-sdk#2735 · 2 comments · Opened Aug 28, 2026
[v2] OAuth discovery validates any /.well-known/openid-configuration document as OIDC, rejecting conforming RFC 8414 metadata Open

Difficulty 4/5 3-5 days Newbie friendliness 58/100

modelcontextprotocol/typescript-sdk#2733 · 1 comment · Opened Aug 28, 2026
StreamableHTTP server transport returns bare 400 for a notification when the request has Connection: close Open

Difficulty 3/5 1-2 days Newbie friendliness 58/100

modelcontextprotocol/typescript-sdk#2730 · 1 comment · 1 reaction · Opened Aug 27, 2026
UriTemplate.match() does not percent-decode extracted values Open

Difficulty 2/5 1-3 hours Newbie friendliness 84/100

modelcontextprotocol/typescript-sdk#2728 · 4 comments · Opened Aug 27, 2026
remove() is a no-op after a handle is renamed, and the entry stays callable Open

Difficulty 3/5 1-2 days Newbie friendliness 78/100

modelcontextprotocol/typescript-sdk#2723 · 1 comment · Opened Aug 26, 2026
[v2] Era-negotiation probe drops spec-conformant server/discover responses (top-level resultType/_meta) and misclassifies modern servers as legacy Open

Difficulty 4/5 3-5 days Newbie friendliness 62/100

modelcontextprotocol/typescript-sdk#2722 · 3 comments · Opened Aug 26, 2026
outputSchema always emitted as JSON Schema draft-07, breaking clients that only accept 2020-12 Open

Difficulty 2/5 1-3 hours Newbie friendliness 82/100

modelcontextprotocol/typescript-sdk#2721 · 4 comments · 2 reactions · Opened Aug 26, 2026
Docs: registerClient's @deprecated notice cites SEP-2577; DCR deprecation is PR #2858 (SEP-2577 is Roots/Sampling/Logging) Open

Difficulty 1/5 Under an hour Newbie friendliness 85/100

modelcontextprotocol/typescript-sdk#2719 · Opened Aug 26, 2026
[v2] Incompatibility with refresh_tokens from Azure when client_id=resource_id Open

v2

Difficulty 3/5 1-2 days Newbie friendliness 72/100

modelcontextprotocol/typescript-sdk#2718 · Opened Aug 26, 2026
Semantics question: how should tool-call telemetry count cancelled or retried `tools/call` requests? Open

Difficulty 4/5 3-5 days Newbie friendliness 48/100

modelcontextprotocol/typescript-sdk#2715 · 1 comment · 1 reaction · Opened Aug 25, 2026
registerTool with zod raw shape: refine/superRefine/transform are silently dropped from validation Open

v1 v2

Difficulty 3/5 1-2 days Newbie friendliness 55/100

modelcontextprotocol/typescript-sdk#2705 · 1 comment · Opened Aug 23, 2026
Stateless StreamableHTTPServerTransport: per-request requirement is invisible through the Node wrapper (500 with empty body) Open

v1 v2

Difficulty 4/5 3-5 days Newbie friendliness 52/100

modelcontextprotocol/typescript-sdk#2704 · 1 comment · Opened Aug 23, 2026
Deno: TS2307 on all .js subpath imports — './*' exports map types to '*.js.d.ts' Open

v1

Difficulty 2/5 1-3 hours Newbie friendliness 84/100

modelcontextprotocol/typescript-sdk#2701 · 2 comments · Opened Aug 22, 2026
Client follows server 3xx into internal/loopback services: redirect SSRF / protocol confusion (bare fetch, no host validation) — same class as python-sdk #3358 Open

v1 v2

Difficulty 4/5 3-5 days Newbie friendliness 52/100

modelcontextprotocol/typescript-sdk#2700 · 1 comment · Opened Aug 22, 2026
`maxTotalTimeout` is never enforced unless a progress notification arrives Open

v1 v2

Difficulty 3/5 1-2 days Newbie friendliness 82/100

modelcontextprotocol/typescript-sdk#2695 · 10 comments · Opened Aug 21, 2026
Resource templates ignore `enabled`: disable() leaves them listed, readable and completable Open

v1 v2

Difficulty 3/5 1-2 days Newbie friendliness 78/100

modelcontextprotocol/typescript-sdk#2693 · 1 comment · Opened Aug 21, 2026
Streamable HTTP server accepts unsafe integer in x-mcp-header field when mirrored header is absent Open

v2

Difficulty 3/5 1-2 days Newbie friendliness 48/100

modelcontextprotocol/typescript-sdk#2689 · Opened Aug 19, 2026
Proposal: warn when a network-facing MCP server starts without authentication Open

auth enhancement needs design v1 v2

Difficulty 5/5 Over a week Newbie friendliness 35/100

modelcontextprotocol/typescript-sdk#2685 · Opened Aug 18, 2026
[v2] StreamableHTTPClientTransport standby GET/SSE stream reconnects forever when the server gracefully idle-closes it ( maxRetries never trips) Open

v1 v2

Difficulty 3/5 1-2 days Newbie friendliness 68/100

modelcontextprotocol/typescript-sdk#2682 · Opened Aug 17, 2026
tools/list emits draft-07 $schema for Zod v4 schemas: toJsonSchemaCompat is called without a target, and mapMiniTarget defaults to 'draft-7' Open

bug v1

Difficulty 3/5 1-2 days Newbie friendliness 68/100

modelcontextprotocol/typescript-sdk#2677 · 8 comments · 1 reaction · Opened Aug 17, 2026
Streamable HTTP SSE tests assume multiple events share one fetch chunk Open

bug good first issue P3 v1 v2

Difficulty 2/5 1-3 hours Newbie friendliness 78/100

modelcontextprotocol/typescript-sdk#2661 · 2 comments · Opened Aug 14, 2026
[v2] StreamableHTTPClientTransport drops SSE stream provenance, so a server-initiated request cannot be attributed to the client request that provoked it Open

enhancement needs design v1 v2

Difficulty 3/5 1-2 days Newbie friendliness 72/100

modelcontextprotocol/typescript-sdk#2659 · Opened Aug 13, 2026
tools/call has no path to a protocol-level "Server errors" response, even for unhandled exceptions Open

enhancement needs design v1 v2

Difficulty 5/5 Over a week Newbie friendliness 35/100

modelcontextprotocol/typescript-sdk#2656 · 1 comment · Opened Aug 13, 2026
[v2] subscriptions/listen holds a stream open even when it has honoured nothing Open

bug P1 ready for work spec-2026-07-28 v2

Difficulty 2/5 1-3 hours Newbie friendliness 78/100

modelcontextprotocol/typescript-sdk#2650 · 2 comments · Opened Aug 12, 2026
[v2] Legacy-era cancel of a resumed request: notifications/cancelled inherits the request's resumptionToken, so the transport swallows the cancellation and opens a rogue resumed GET Open

v1 v2

Difficulty 2/5 1-3 hours Newbie friendliness 88/100

modelcontextprotocol/typescript-sdk#2646 · 1 comment · Opened Aug 11, 2026
[v2] StreamableHTTPClientTransport: auth awaits in _send are un-abortable — requestSignal cannot cancel token()/onUnauthorized/metadata-discovery parks Open

spec-2026-07-28 v2

Difficulty 4/5 3-5 days Newbie friendliness 45/100

modelcontextprotocol/typescript-sdk#2643 · Opened Aug 11, 2026
[v2] Client.listen() rejections escape as process-level unhandledRejection while the send is in flight; a parked send hangs listen() past its ack timeout Open

spec-2026-07-28 v2

Difficulty 3/5 1-2 days Newbie friendliness 58/100

modelcontextprotocol/typescript-sdk#2641 · Opened Aug 11, 2026

A short digest of beginner-friendly GitHub issues.