NousResearch/hermes-agent

Streamable HTTP MCP client connection and negotiation fixes

Cluster 114350. Data as of 2026-10-26 12:29 UTC

Nothing open on GitHub. Fix merged in #114817 on 18 Sep 2026. Check it covers your case.

open issues

open PRs

items grouped

Known?: Yes. 3 related items grouped here, 1 issue already closed.
Fix event: A fix was merged to main in PR #114817. Check it covers your case. No release data is tracked.
Tracker: The maintainers' tracker marks this resolved, deciding PR #114817. That is separate from the fix event.
Still open: Nothing open on GitHub.

Next step: read #114817, then check it covers your case.

Read #114817 Pick up a Lab task

These issues and fixes address bugs in the Streamable HTTP MCP client: improving error messages to surface HTTP status, URL, and body on failures, and correcting protocol version negotiation during the handshake.

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.

#114817 fix(mcp): Streamable HTTP connect failures name the HTTP status, URL and body behind "Server returned an error response" (#113359, #114350, salvage #113392)

merged to main

files: tests/tools/test_mcp_protocol_negotiation.py, tests/tools/test_mcp_sse_fallback.py, tools/mcp_tool.py, tools/mcp_tool_errors.py, tools/mcp_tool_transport.py, website/docs/user-guide/features/mcp.md

1 PR closed without merging

From the close comments: superseded by another PR 1

#114381 fix(mcp): don't advertise an unnegotiated MCP-Protocol-Version on the streamable HTTP handshake · superseded by another PR → #113392

Closed issues · 1

Closed#114350[Bug]: Streamable HTTP MCP client fails against a server that negotiates a non-latest protocol version

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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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: #114817
Closed issues: 1
Attempts: 1 PR closed without merging
Fix link checked: 18 Sep 2026

For your agent

The same facts, typed.

cluster/114350.json
cluster/114350.md