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NousResearch/hermes-agent

Anthropic malformed JSON streaming tool call fixes

Cluster 107830 · agent. Data as of

1 open item. Fix merged in #109324 on 14 Sep 2026. Check it covers your case.

The short answer

0open issues
1open PR
6items grouped
Known?
Yes. 6 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #109324. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #109324. That is separate from the fix event.
Still open
0 issues and 1 PR.

Multiple fixes and approaches addressing a bug where Anthropic streaming tool calls fail permanently due to malformed JSON output. The cluster explores several strategies including fallback to buffered requests, retries, and disabling fine-grained tool streaming.

Open issues0

No open issues.

Open PRs1

  • PR#107864fix(anthropic): recover malformed streamed tool JSON

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #109324 fix(anthropic): malformed streamed tool JSON retries with buffered tool input (#107830, salvage #107864)

    merged to main

    files: agent/anthropic_adapter.py, agent/api_error_summary.py, agent/chat_completion_helpers.py, run_agent.py, tests/agent/test_streaming.py

3 PRs closed without merging

From the close comments: superseded by another PR 2 · partial fix 1

  • #107833 fix(anthropic): fall back to messages.create() when streaming fails on malformed JSON (#107830) · partial fix → #99692
  • #108583 fix(anthropic): disable fine-grained tool streaming by default and fallback on malformed JSON (#107830) · superseded by another PR → #109324, #107830
  • #109056 fix(anthropic): remove fine-grained-tool-streaming beta to prevent malformed JSON streaming failures (fixes #107830) · superseded by another PR → #109324, #107830, #107833
Closed issues · 1
  • Closed#107830[Bug]:Streaming tool calls fail permanently with "expected value at line 1 column 11" when Anthropic emits malformed JSON
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.33: the share of item pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. 1.00 means every pair is linked.

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At a glance

Subsystem
agent
Merged PRs
#109324
Closed issues
1
Attempts
3 PRs closed without merging
Fix link checked
14 Sep 2026

For your agent

The same facts, typed.

cluster/107830.json
cluster/107830.md