PR #14438: fix(agent): stream copilot ACP chat completions

• Repository: NousResearch/hermes-agent
• Author: sgaofen
• State: open | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/14438

Description (problem / solution / changelog)

Issue

Fixes #14437.

Root cause

Copilot ACP uses the chat-completions path, where Hermes requests stream=true. The ACP shim ignored that argument and returned a one-shot SimpleNamespace completion, so the streaming loop tried to iterate a non-iterable object and raised TypeError. Its parsed tool calls also did not quite match OpenAI SDK model behavior for downstream compatibility.

Fix

The ACP shim now returns OpenAI-style iterable stream chunks when stream=true, including text deltas, tool-call deltas with indices, finish_reason, and a final usage chunk. Parsed ACP tool calls are also constructed as OpenAI SDK ChatCompletionMessageToolCall objects while preserving Hermes call_id metadata.

This is a fresh main-based salvage of the same failure class as stale/dirty PRs #12274, #9578, and #13071, with focused current regression coverage.

Tests

• /Users/stephenyu/Documents/hermes-agent/.venv/bin/python -m pytest tests/agent/test_copilot_acp_client.py -q --tb=short
• /Users/stephenyu/Documents/hermes-agent/.venv/bin/python -m pytest tests/run_agent/test_run_agent_codex_responses.py::test_copilot_acp_stays_on_chat_completions_for_gpt_5_models tests/run_agent/test_run_agent.py::test_aiagent_uses_copilot_acp_client -q --tb=short
• /Users/stephenyu/Documents/hermes-agent/.venv/bin/python inline streaming smoke test with patched CopilotACPClient._run_prompt
• git diff --check

Changed files

• agent/copilot_acp_client.py (modified, +77/-8)
• tests/agent/test_copilot_acp_client.py (modified, +105/-0)

PR #14442: fix(copilot-acp): raise NotImplementedError on stream=True to prevent SimpleNamespace iteration crash

• Repository: NousResearch/hermes-agent
• Author: Bartok9
• State: open | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/14442

Description (problem / solution / changelog)

Problem

Fixes #14437.

When using the copilot-acp provider, any request crashes with:

RuntimeError: 'types.SimpleNamespace' object is not iterable

Root cause: The agent loop calls .chat.completions.create(stream=True) by default (via _interruptible_streaming_api_call). The copilot-acp provider's _create_chat_completion accepted **_ and silently ignored the stream kwarg, returning a SimpleNamespace response object directly. The streaming loop then did:

for chunk in stream:  # stream is a SimpleNamespace, not an iterator

…crashing immediately with the not iterable error before any response was delivered.

Fix

Add stream as an explicit keyword argument in _create_chat_completion and raise NotImplementedError("stream not supported for copilot-acp provider") when True.

The error message matches the pattern the agent loop already checks in _interruptible_streaming_api_call:

_is_stream_unsupported = (
    "stream" in _err_lower
    and "not supported" in _err_lower
)
if _is_stream_unsupported:
    self._disable_streaming = True  # retries without streaming

This means on the first request Hermes auto-detects that copilot-acp doesn't support streaming, disables it for the session, and retries — so the conversation continues uninterrupted with no user intervention needed.

Testing

from agent.copilot_acp_client import CopilotACPClient
import pytest

client = CopilotACPClient(acp_command="echo")

# stream=False (default) — should NOT raise
# (will fail to connect to echo, but won't crash on iteration)

# stream=True — should raise NotImplementedError with correct message
try:
    client.chat.completions.create(
        model="copilot",
        messages=[{"role": "user", "content": "hi"}],
        stream=True,
    )
    assert False, "Should have raised"
except NotImplementedError as e:
    assert "stream not supported" in str(e).lower()

Changed files

• agent/copilot_acp_client.py (modified, +10/-0)