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Merged
merged 6 commits into from
Sep 23, 2025
Merged

Fastmcp logging progress example #1270

merged 6 commits into from
Sep 23, 2025
+33 −0

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stevebillings
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Added a FastMCP example that shows how to send log messages and progress reports back to the client during tool execution.

The new example is examples/fastmcp/logging_and_progress.py. The tool function receives a context argument and calls its .info() and .report_progress() methods. It is based off of simple_echo.py; I copied that example, and added to the tool function a context argument, logging, and progress reporting.

Motivation and Context

As a total newbie, I had a little trouble getting the context argument to receive a value. I couldn't find an example showing how a tool should get the context argument in this repo, and I was slow to realize that I needed to read the FastMCP documentation. Because I hadn't pointed it to the FastMCP documenation, Claude Code generated a declaration for the context argument that didn't work (it typed the context argument as Optional, which understandably causes the SDK not to recognize the argument as the context argument). Seems obvious in retrospect, but it wasn't obvious to me at first.

I also learned while testing of the potential race condition with notifications sent near the end of a tool call: Since the client SDK code (src/mcp/shared/session.py) processes progress notifications asynchronously, if the tool function returns very soon after the final call to report_progress, the client doesn't reliably receive that final progress update. Adding the final sleep helps ensure the client will process the final progress update. I assume this is intended behavior but hope that the sleep in the example might draw users' attention to something they should probably be aware of.

How Has This Been Tested?

I have tested equivalent lines of code in the MCP server and client I am developing, and I have tested the new example (MCP server) using modelcontextprotocol/inspector.

Breaking Changes

None.

Types of changes

It simply adds one example code source file.

  • Bug fix (non-breaking change which fixes an issue)
  • New feature (non-breaking change which adds functionality)
  • Breaking change (fix or feature that would cause existing functionality to change)
  • Documentation update

Checklist

  • I have read the MCP Documentation
  • My code follows the repository's style guidelines
  • New and existing tests pass locally
  • I have added appropriate error handling [I believe I have successfully followed simple_echo.py's lead on this and added no error handling.]
  • I have added or updated documentation as needed [I believe I have successfully followed simple_echo.py's lead on this and added no documentation.]

Additional context

Hopefully I got this right; happy to adjust if I didn't.

@stevebillings
Added a FastMCP example that shows how to send log messages and progr…
5ab3a37 
…ess reports back to the client during tool execution.
@stevebillings
added brief sleep at the end of the tool function to highlight the po…
8daf7f0 
…tential race condition affecting notifications sent near the end of a tool function.
@stevebillings
improved server name and comments
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@stevebillings stevebillings requested a review from a team as a code owner August 13, 2025 20:52
@stevebillings stevebillings requested a review from Kludex August 13, 2025 20:52
@stevebillings stevebillings changed the title Fastmpc logging progress example Fastmcp logging progress example Aug 13, 2025
felixweinberger
felixweinberger approved these changes Sep 23, 2025
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Seems reasonable, thank you for this contribution and converting your experience here into an example!

@felixweinberger felixweinberger merged commit 03e19f1 into modelcontextprotocol:main Sep 23, 2025
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@felixweinberger felixweinberger added the documentation Improvements or additions to documentation label Sep 23, 2025
rbehal pushed a commit to gumloop/gumloop-mcp that referenced this pull request Sep 25, 2025
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[GMLP-5458] Sync upstream (#5)
0206b4d 
* Add regression test for stateless request memory cleanup (modelcontextprotocol#1140)

* Implement RFC9728 - Support WWW-Authenticate header by MCP client (modelcontextprotocol#1071)

* Add streamable HTTP starlette example to Python SDK docs (modelcontextprotocol#1111)

* fix markdown error in README in main (modelcontextprotocol#1147)

* README - replace code snippets with examples - add lowlevel to snippets (modelcontextprotocol#1150)

* README - replace code snippets with examples - streamable http (modelcontextprotocol#1155)

* chore: don't allow users to create issues outside the templates (modelcontextprotocol#1163)

* Tests(cli): Add coverage for helper functions (modelcontextprotocol#635)

* Docs: Update CallToolResult parsing in README (modelcontextprotocol#812)

Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>

* docs: add pre-commit install guide on CONTRIBUTING.md (modelcontextprotocol#995)

Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>

* fix flaky fix-test_streamablehttp_client_resumption test (modelcontextprotocol#1166)

* README - replace code snippets with examples -- auth examples (modelcontextprotocol#1164)

* Support falling back to OIDC metadata for auth (modelcontextprotocol#1061)

* Add CODEOWNERS file for sdk (modelcontextprotocol#1169)

* fix flaky test test_88_random_error (modelcontextprotocol#1171)

* Make sure `RequestId` is not coerced as `int` (modelcontextprotocol#1178)

* Fix: Replace threading.Lock with anyio.Lock for Ray deployment compatibility (modelcontextprotocol#1151)

* fix: fix OAuth flow request object handling (modelcontextprotocol#1174)

* update codeowners group (modelcontextprotocol#1191)

* fix: perform auth server metadata discovery fallbacks on any 4xx (modelcontextprotocol#1193)

* server: skip duplicate response on CancelledError (modelcontextprotocol#1153)

Co-authored-by: ihrpr <inna@anthropic.com>

* Unpack settings in FastMCP (modelcontextprotocol#1198)

* chore: Remove unused prompt_manager.py file (modelcontextprotocol#1229)

Co-authored-by: Tapan Chugh <tapanc@cs.washington.edu>

* Improved supported for ProtectedResourceMetadata (modelcontextprotocol#1235)

Co-authored-by: Paul Carleton <paulcarletonjr@gmail.com>

* chore: Remove unused variable notification_options (modelcontextprotocol#1238)

* Improve README around the Context object (modelcontextprotocol#1203)

* fix: allow to pass `list[str]` to `token_endpoint_auth_signing_alg_values_supported` (modelcontextprotocol#1226)

* Remove strict validation on `response_modes_supported` member of `OAuthMetadata` (modelcontextprotocol#1243)

* Add pyright strict mode on the whole project (modelcontextprotocol#1254)

* Consistent casing for default headers Accept and Content-Type (modelcontextprotocol#1263)

* Update dependencies and fix type issues (modelcontextprotocol#1268)

Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>

* fix: prevent async generator cleanup errors in StreamableHTTP transport (modelcontextprotocol#1271)

Co-authored-by: David Soria Parra <167242713+dsp-ant@users.noreply.github.com>

* chore: uncomment .idea/ in .gitignore (modelcontextprotocol#1287)

Co-authored-by: Claude <noreply@anthropic.com>

* docs: clarify streamable_http_path configuration when mounting servers (modelcontextprotocol#1172)

* feat: Add CORS configuration for browser-based MCP clients (modelcontextprotocol#1059)

Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>
Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>

* Added Audio to FastMCP (modelcontextprotocol#1130)

* fix: avoid uncessary retries in OAuth authenticated requests (modelcontextprotocol#1206)

Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>

* Add PATHEXT to default STDIO env vars in windows (modelcontextprotocol#1256)

* fix: error too many values to unpack (expected 2) (modelcontextprotocol#1279)

Signed-off-by: San Nguyen <vinhsannguyen91@gmail.com>
Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>
Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>

* SDK Parity: Avoid Parsing Server Response for non-JsonRPCMessage Requests (modelcontextprotocol#1290)

* types: Setting default value for method: Literal (modelcontextprotocol#1292)

* changes structured temperature to not deadly (modelcontextprotocol#1328)

* Update simple-resource example to use non-deprecated read_resource return type (modelcontextprotocol#1331)

Co-authored-by: Claude <noreply@anthropic.com>

* docs: Update README to include link to API docs for modelcontextprotocol#1329 (modelcontextprotocol#1330)

* Allow ping requests before initialization (modelcontextprotocol#1312)

* Python lint: Ruff rules for pylint and code complexity (modelcontextprotocol#525)

* Fix context injection for resources and prompts (modelcontextprotocol#1336)

* fix(fastmcp): propagate mimeType in resource template list (modelcontextprotocol#1186)

Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>

* fix: allow elicitations accepted without content (modelcontextprotocol#1285)

Co-authored-by: Olivier Schiavo <olivier.schiavo@wengo.com>

* Use --frozen in pre-commit config (modelcontextprotocol#1375)

* Return HTTP 403 for invalid Origin headers (modelcontextprotocol#1353)

* Add test for ProtectedResourceMetadataParsing (modelcontextprotocol#1236)

Co-authored-by: Paul Carleton <paulcarletonjr@gmail.com>
Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>
Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>

* Fastmcp logging progress example (modelcontextprotocol#1270)

Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>

* feat: add paginated list decorators for prompts, resources, and tools (modelcontextprotocol#1286)

Co-authored-by: Claude <noreply@anthropic.com>

* Remove "unconditionally" from conditional description (modelcontextprotocol#1289)

* Use streamable-http consistently in examples (modelcontextprotocol#1389)

* feat: Add SDK support for SEP-1034 default values in elicitation schemas (modelcontextprotocol#1337)

Co-authored-by: Tapan Chugh <tapanc@cs.washington.edu>
Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>

* Implementation of SEP 973 - Additional metadata + icons support (modelcontextprotocol#1357)

* Merge upstream/main with custom filtering

---------

Signed-off-by: San Nguyen <vinhsannguyen91@gmail.com>
Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>
Co-authored-by: yurikunash <143175350+yurikunash@users.noreply.github.com>
Co-authored-by: Pamela Fox <pamela.fox@gmail.com>
Co-authored-by: Inna Harper <inna.hrpr@gmail.com>
Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>
Co-authored-by: Ian Davenport <49379192+davenpi@users.noreply.github.com>
Co-authored-by: Dagang Wei <functicons@gmail.com>
Co-authored-by: Felix Weinberger <fweinberger@anthropic.com>
Co-authored-by: Stanley Law <stanleylkal@gmail.com>
Co-authored-by: Luca Chang <131398524+LucaButBoring@users.noreply.github.com>
Co-authored-by: leweng <leweng@nvidia.com>
Co-authored-by: Clare Liguori <liguori@amazon.com>
Co-authored-by: lukacf <luka@peltarion.com>
Co-authored-by: ihrpr <inna@anthropic.com>
Co-authored-by: Tapan Chugh <chugh.tapan@gmail.com>
Co-authored-by: Tapan Chugh <tapanc@cs.washington.edu>
Co-authored-by: Yann Jouanin <4557670+yannj-fr@users.noreply.github.com>
Co-authored-by: Paul Carleton <paulcarletonjr@gmail.com>
Co-authored-by: Sreenath Somarajapuram <somarajapuram@gmail.com>
Co-authored-by: Omer Korner <omerkorner@gmail.com>
Co-authored-by: joesavage-silabs <159480754+joesavage-silabs@users.noreply.github.com>
Co-authored-by: Gregory L <gregory.linford@mistral.ai>
Co-authored-by: David Soria Parra <167242713+dsp-ant@users.noreply.github.com>
Co-authored-by: Moustapha Ebnou <155577789+mous222@users.noreply.github.com>
Co-authored-by: Max Isbey <224885523+maxisbey@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jerome <jerome@anthropic.com>
Co-authored-by: xavier <84836280+dragonier23@users.noreply.github.com>
Co-authored-by: keurcien <keurcien.luu@gmail.com>
Co-authored-by: Tim Esler <tim.esler@gmail.com>
Co-authored-by: San Nguyen <22189661+sandangel@users.noreply.github.com>
Co-authored-by: Justin Wang <89049861+justin-yi-wang@users.noreply.github.com>
Co-authored-by: jess <jessachandler@gmail.com>
Co-authored-by: Peter Alexander <pja@anthropic.com>
Co-authored-by: Reid Geyer <12072650+reidg44@users.noreply.github.com>
Co-authored-by: Eleftheria Stein-Kousathana <eleftheria.kousathana@gmail.com>
Co-authored-by: Christian Clauss <cclauss@me.com>
Co-authored-by: pchoudhury22 <pchoudhury22@apple.com>
Co-authored-by: owengo <owengo@users.noreply.github.com>
Co-authored-by: Olivier Schiavo <olivier.schiavo@wengo.com>
Co-authored-by: Steve Billings <billings.steve@gmail.com>
Co-authored-by: Mike Salvatore <mike.s.salvatore@gmail.com>
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@felixweinberger felixweinberger felixweinberger approved these changes

@Kludex Kludex Awaiting requested review from Kludex Kludex is a code owner automatically assigned from modelcontextprotocol/python-sdk

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