Issues

• A proxy served over stdio forwards only some of the backend's ctx.log() messages

  bugserver
  PrefectHQ/fastmcp#6303 · Filter by author alpaylan opened on Nov 3, 2026
  1

• A supporting file named SKILL.md in a subfolder is listed as a separate skill and makes sync_skills() fail

  bug
  PrefectHQ/fastmcp#6302 · Filter by author alpaylan opened on Nov 3, 2026
  1

• Versionless lookup through a mount does not fall back to the enabled version when the child server has list-filtering middleware

  bugserver
  PrefectHQ/fastmcp#6301 · Filter by author alpaylan opened on Nov 3, 2026

• ctx.elicit() multi-select with [[...]] sends items without "type": "string", which the 2025-11-25 schema requires

  bugserver
  PrefectHQ/fastmcp#6300 · Filter by author alpaylan opened on Nov 3, 2026
  1

• logging/setLevel is ignored for ctx.log() calls from tools of a mounted server

  bugserver
  PrefectHQ/fastmcp#6299 · Filter by author alpaylan opened on Nov 3, 2026
  1

• Client(mode="legacy", cache=CacheConfig(default_ttl_ms=...)) serves cached listings, although the cache is documented as inert on legacy connections

  bugclient
  PrefectHQ/fastmcp#6298 · Filter by author alpaylan opened on Nov 3, 2026
  1

• OAuth client redirect carries two iss parameters when the registered redirect_uri already repeats iss

  authbugsecurity
  PrefectHQ/fastmcp#6297 · Filter by author alpaylan opened on Nov 3, 2026

• OAuth client redirect turns a registered myapp:// redirect_uri into myapp:?...

  authbug
  PrefectHQ/fastmcp#6296 · Filter by author alpaylan opened on Nov 3, 2026

• Redirect URI helpers accept raw-string URIs that resolve to a different host or path (backslash, trailing space/C0, IPv4 shorthand, percent-encoded or IDNA hosts)

  authbughigh-prioritysecurity
  PrefectHQ/fastmcp#6295 · Filter by author alpaylan opened on Nov 3, 2026

• generate-cli gives user_id and userId the same flag

  bugcli
  PrefectHQ/fastmcp#6294 · Filter by author andreivince opened on Nov 3, 2026
  1

  

• Hidden parameter renamed to a visible sibling leaks its default_factory into the visible parameter

  bug
  PrefectHQ/fastmcp#6285 · Filter by author shi-felix opened on Nov 3, 2026

• BM25 search transform crashes with KeyError after a tool rename that preserves searchable text

  bugserver
  PrefectHQ/fastmcp#6284 · Filter by author shi-felix opened on Nov 3, 2026

• Tools docs say bytes are returned as an EmbeddedResource blob, but they're sent as TextContent

  documentation
  PrefectHQ/fastmcp#6274 · Filter by author DivyaNarahari97 opened on Nov 3, 2026
  1

• mask_error_details does not mask prompt handler exceptions

  bugserver
  PrefectHQ/fastmcp#6273 · Filter by author maxmorrish opened on Nov 3, 2026
  2

• Resource listing fetches proxy tools without the optional renderer

  bugmcp apps
  PrefectHQ/fastmcp#6269 · Filter by author andreivince opened on Nov 3, 2026

• OpenAPI rejects declared 202 JSON success after executing POST

  PrefectHQ/fastmcp#6265 · Filter by author PennEwan opened on Nov 2, 2026

• Add OpenStack Keystone Token Validator

  authenhancement
  PrefectHQ/fastmcp#6262 · Filter by author bkranendonk opened on Nov 2, 2026
  1

  

• Add configuration for _meta.fastmcp data

  enhancementserver
  PrefectHQ/fastmcp#6236 · Filter by author jeffsawatzky opened on Nov 2, 2026

• Gemini discovery selects user server over same-name workspace server

  bugcli
  PrefectHQ/fastmcp#6230 · Filter by author RoryGlenn opened on Nov 2, 2026

• FileSystemProvider: component construction failures hide healthy tools

  bugprovider
  PrefectHQ/fastmcp#6209 · Filter by author PennEwan opened on Nov 1, 2026

• Background tools stop after the first failure despite a Docket retry policy

  bugtasks
  PrefectHQ/fastmcp#6202 · Filter by author PennEwan opened on Nov 1, 2026

• session: UserSession on a resource or resource template fails at registration

  bugserver
  PrefectHQ/fastmcp#6197 · Filter by author arjunprabhulal opened on Oct 31, 2026

• Single-server MCPConfig tag filters don't see tags added in tools

  bug
  PrefectHQ/fastmcp#6196 · Filter by author arjunprabhulal opened on Oct 31, 2026

• Unconvertible prompt and resource template arguments return internal error instead of invalid params

  bug
  PrefectHQ/fastmcp#6194 · Filter by author DivyaNarahari97 opened on Oct 31, 2026

• Transformed tools mutate visible schema defaults across calls

  bug
  PrefectHQ/fastmcp#6183 · Filter by author priy-anshugupta opened on Oct 31, 2026