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Sweep 22 Oct 2026 · 04:32Z Build v2.1.308 527 read Stable v2.1.308 Latest v2.1.308 Next v2.1.308 Feeds RSS JSON llms.txt llms-full.txt Unofficial
HomeDocsClaude Developer Platform 22 Oct 2026
One change · api

server-tools changedagents-and-tools/tool-use/server-tools

Nearest release: v2.1.308, published 2 hours after this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.

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From line 10 where the diff opens
First seen 14 Aug 2026 this site's first read of the page
Recorded edits13to this page, all time

The whole hunk

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1010 
1111The `server_tool_use` block appears in Claude's response when a server-executed tool runs. Its `id` field uses the `srvtoolu_` prefix to distinguish it from client tool calls:
1212 
13```json
13```text wrap
1414{
1515 "type": "server_tool_use",
1616 "id": "srvtoolu_01A2B3C4D5E6F7G8H9",
from line 405
405405 With [programmatic tool calling](https://platform.claude.com/docs/en/agents-and-tools/tool-use/programmatic-tool-calling), the same response shape means something different. The client `tool_use` block comes from code that is running in the `code_execution` tool rather than from Claude directly, and its `caller` field names the `code_execution` block that called it. That code has already started: it is paused waiting for your `tool_result` blocks, and sending them resumes the execution instead of starting a deferred tool. The `code_execution` block's own result block arrives once the code completes, which can take more than one round of tool results. The follow-up user message itself is the same in both cases; with programmatic tool calling, also pass back the `id` from the response's `container` field, as that page shows.
406406</Note>
407407 
408```json
408```text wrap
409409{
410410 "stop_reason": "tool_use",
411411 "content": [
from line 446
446446 
447447The API attaches your results to the still-open assistant turn, runs the deferred server tool (for paused code execution, resumes it), and then lets Claude continue. For a server tool Claude called directly, the next response starts with the result block that answers the previous response's `server_tool_use` `id`, followed by the newly generated content and a fresh `stop_reason`:
448448 
449```json
449```text wrap
450450{
451451 "stop_reason": "end_turn",
452452 "content": [
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