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NousResearch/hermes-agent

MCP json.dumps ensure_ascii handling for non-ASCII results

Cluster 10234. Data as of

Nothing open on GitHub. Fix merged in #10512 on 15 Apr 2026. Check it covers your case.

The short answer

0open issues
0open PRs
3items grouped
Known?
Yes. 3 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #10512. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #10512. That is separate from the fix event.
Still open
Nothing open on GitHub.

One issue reports that Chinese MCP tool results use about three times as many tokens, attributing this to ensure_ascii being set to True in json.dumps in mcp_tool.py. The two pull requests both change ensure_ascii in MCP json.dumps calls, but one titles it as adding True and the other as False, so their intended settings appear to differ.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

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

  • #10512 fix: add ensure_ascii=False to all MCP json.dumps calls

    merged to main

    files: tools/mcp_tool.py

1 PR closed without merging

From the close comments: superseded by another PR 1

  • #10329 fix(mcp): add ensure_ascii=True to all json.dumps calls (#10234) · superseded by another PR → #10512
Closed issues · 1
  • Closed#10234When Hermes calls the MCP tool, if the returned result is in Chinese, it will consume three times as many tokens. This is because the ensure_ascii parameter in json.dumps within mcp_tool.py is set to True.
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 0.67: 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

Merged PRs
#10512
Closed issues
1
Attempts
1 PR closed without merging
Fix link checked
15 Apr 2026. This confirmation is old and may be out of date (a revert or reopen would not have invalidated it here); re-verify.

For your agent

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cluster/10234.json
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