Follow Discord
Sweep 03 Oct 2026 · 20:28Z Build v2.1.289 510 read Stable v2.1.285 Latest v2.1.289 Next v2.1.289 Feeds RSS JSON llms.txt llms-full.txt Unofficial
HomeDocsClaude Code CLI 5 Oct 2026
One change · claude-code

Agent SDK reference - Python changedagent-sdk/python

Upstream edited this page at 5 Oct 2026 01:07 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 5 Oct 2026 01:37 UTC.

Upstream edited
Recorded here
Lines+2added
Lines−1removed
From line 2,535 where the diff opens
First seen 14 Aug 2026 this site's first read of the page
Recorded edits41to this page, all time

The whole hunk

from line 2535, old and new numbered
/
lines
from line 2535
25352535 "speed": str | None,
25362536 "iterations": Any | None,
25372537 "output_tokens_details": {"thinking_tokens": int | None} | None,
2538 "fallback_credit": Any | None,
25382539 },
25392540 "toolStats": { # Aggregate tool activity for the run
25402541 "readCount": int,
from line 2586
25852586 
25862587On the `completed` variant, `resolvedModel` names the model the subagent started on, which can differ from the requested `model` input when [`availableModels`](/docs/en/model-config#restrict-model-selection) or another override applies. This field requires Claude Code v2.1.174 or later. On the `async_launched` variant, `resolvedModel` names the model in use when the agent moved to the background, so a swap that happened before backgrounding is reflected there. The `modelsUsed` field on both variants lists the models used in order, with consecutive repeats collapsed; it's set only when the model was swapped mid-run. `modelsUsed` and the backgrounding-time `resolvedModel` behavior require Claude Code v2.1.212 or later.
25872588 
2588Claude Code fills `usage` and `totalTokens` from the subagent's final API request, not from the whole run. When present, `thinking_tokens` under `output_tokens_details` in `usage` is the number of that request's output tokens that were thinking tokens. The `output_tokens_details` key requires Python SDK v0.2.136 or later, which bundles Claude Code v2.1.228.
2589Claude Code fills `usage` and `totalTokens` from the subagent's final API request, not from the whole run. When present, `thinking_tokens` under `output_tokens_details` in `usage` is the number of that request's output tokens that were thinking tokens. The `output_tokens_details` key requires Python SDK v0.2.136 or later, which bundles Claude Code v2.1.228. The `fallback_credit` key requires Python SDK v0.2.162 or later, which bundles Claude Code v2.1.285.
25892590 
25902591### AskUserQuestion
25912592 
Feedback