Fix OpenAI streaming tool calls being split into two entries

[dpage]

Summary

• OpenAIClient._read_responses_stream() accumulated Responses API (/v1/responses) streamed function-call arguments in a tool_calls_data dict keyed by call_id. But per OpenAI's Responses API streaming event reference, response.function_call_arguments.delta events carry item_id, output_index, delta and sequence_number — there is no call_id on that event. data.get('call_id', '') always evaluated to '', so every delta missed the entry seeded by the preceding response.output_item.added event and accumulated into a second, empty-name entry instead — one tool call came back as two separate ToolCalls (name with no arguments, and arguments with no name).
• Correlates delta events on item_id (matching item.id from response.output_item.added) instead, while still carrying the real call_id through so the emitted ToolCall.id (used later to reference the call, e.g. 'call_id': tc.id when replaying tool calls back to the API) is correct.

Test plan

• Added two scenarios to web/pgadmin/llm/tests/test_openai_stream.py covering a single streamed tool call and two parallel tool calls, using fake Responses API SSE events.
• Confirmed both new tests fail against the pre-fix call_id-keyed logic and pass with the fix.
• pycodestyle clean on the changed/added files.

Closes #10348

Summary by CodeRabbit

• Bug Fixes

  • Improved handling of streamed AI tool calls.
  • Preserved correct associations for parallel tool calls, including their IDs, names, and arguments.

• Tests

  • Added coverage for streamed function-call handling and argument accumulation.

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Run ID: 6435cd1b-7b18-4521-b995-bd66db0c3929

📥 Commits

Reviewing files that changed from the base of the PR and between bc58657 and 0f7c2ae.

📒 Files selected for processing (2)

• web/pgadmin/llm/providers/openai.py
• web/pgadmin/llm/tests/test_openai_stream.py

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Walkthrough

The Responses API stream parser now correlates function-call argument deltas by item_id. Final tool calls retain their call_id, name, and parsed arguments. Tests cover single and parallel streamed function calls.

Changes

Responses tool-call correlation

Layer / File(s)	Summary
Correlate and construct tool calls web/pgadmin/llm/providers/openai.py	The parser keys accumulated tool-call data by item_id, stores call_id separately, and uses it when constructing final ToolCall objects.
Validate streamed tool calls web/pgadmin/llm/tests/test_openai_stream.py	Tests verify argument accumulation, tool-call identifiers, names, parsed arguments, and separate handling of parallel function calls.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to 0f7c2

This localized fix corrects streamed tool-call assembly and adds regression coverage for single and parallel calls; no actionable merge-blocking risk remains beyond normal checks and review.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 3 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the primary change: preventing OpenAI streaming tool calls from splitting into separate entries.
Linked Issues check	✅ Passed	The changes satisfy issue #10348 by correlating argument delta events with response.output_item.added events using item_id, preserving call_id for ToolCall.id, and adding coverage for single and paral…
Out of Scope Changes check	✅ Passed	The code changes and tests are directly related to the linked issue and PR objectives. No unrelated changes are present.

Full details: Linked Issues check

Explanation

The changes satisfy issue #10348 by correlating argument delta events with response.output_item.added events using item_id, preserving call_id for ToolCall.id, and adding coverage for single and parallel tool calls.

• Fix all pre-merge checks with AI

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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