fastmcp/dev-docs/v4-notes
nate nowack 2a2080c6c7
add independent client groups (#4904)
* feat(client): add experimental independent client groups

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* refactor(client): narrow client group naming policy

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* fix(client): avoid repeated discovery for unknown tools

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* feat(client): expose client group tool routes

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* docs(client): compare client and session groups

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* docs(client): clarify modern session group gap

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* refactor(client): align client group call signatures with Client

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* docs(client): cross-link client groups from multi-server config docs

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* refactor(client): promote client group out of experimental

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* fix(client): harden client group invariants

Immutable membership, race-free group entry, and per-route connection checks so one dead server does not fail calls routed to healthy servers.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* test(client): satisfy ty on immutable membership test

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* perf(client): connect group clients concurrently

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

* fix(client): refresh group catalog past client response caches

Explicit group.list_tools() now defaults to cache_mode='refresh' via a new cache_mode parameter on Client.list_tools, so a cache-hinted server cannot leave the documented refresh mechanism serving a stale catalog. Lazy cold-start discovery still allows cache hits.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DrQJXPeMepQgJay5xF91yE

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Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-08-27 21:21:48 -05:00
..
background-tasks.md Unpublish v4 development notes; prep docs for beta 1 (#4644) 2026-07-26 14:08:34 -04:00
change-register.md Move to the stable MCP Python SDK 2.0.0 (#4655) 2026-07-28 16:31:49 -04:00
client-groups.md add independent client groups (#4904) 2026-08-27 21:21:48 -05:00
feature-program.md feat: Add telemetry interop mode for FastMCP (#4046) 2026-07-27 16:05:29 -04:00
index.md docs: prepare FastMCP 4 beta 4 (#4914) 2026-08-26 17:57:52 -05:00
known-gaps.md docs: prepare FastMCP 4 beta 3 (#4840) 2026-08-14 13:33:22 -04:00
protocol-2026.md feat: Add telemetry interop mode for FastMCP (#4046) 2026-07-27 16:05:29 -04:00
stateless-session-state.md Unpublish v4 development notes; prep docs for beta 1 (#4644) 2026-07-26 14:08:34 -04:00