fix(streaming): forward tool args on execution-end event

[larock22]

What

Forward the tool-call arguments on the streaming tool-execution-end handler
instead of hardcoding an empty dict.

 self.tool_result_callback(
     tool_name,
     status,
-    {},
+    event_obj.args or {},
     event_obj.result,
     duration_ms,
 )

Why

For completed tools, _handle_stream_tool_execution_end passed {} as the args
to tool_result_callback. Per-tool renderers that derive their panel display
from args therefore had nothing to work with. The most visible symptom: the
read_file result panel builds its filename/path solely from
args["filepath"], so with empty args it rendered the literal string
"unknown" in the tool-output bar for every successful read.

Safety / compatibility

event_obj.args or {} is None-safe. On a tinyagent build where
ToolExecutionEndEvent does not carry args, event_obj.args is None and the
expression yields {} — identical to today's behaviour, no regression. Once
tinyagent populates the field, the real filepath flows through automatically with
no further change here.

Dependency

The end-to-end fix needs tinyagent to expose args on ToolExecutionEndEvent
(it currently only lives on the Start/Update events). Tracked upstream in
alchemiststudiosDOTai/tinyAgent#43. This PR is the consumer half and is safe to
merge independently ahead of that.

Updated streaming tool execution end handling so tool_result_callback now receives event_obj.args or {} instead of a hardcoded empty dict.

This preserves state needed by per-tool renderers and message/tool-call output (for example, allowing completed read_file calls to surface their filepath instead of "unknown"), while remaining safe when ToolExecutionEndEvent.args is unavailable.

Type safety is unchanged functionally, but the new None-fallback avoids regressions on builds that have not yet adopted the upstream event field.

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• src/tunacode/core/agents/agent_components/agent_streaming.py

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GitHub Actions: Empty Directory Check / 0_Check for Empty_Only-init Directories.txt: fix(streaming): forward tool args on execution-end event

Conclusion: failure

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---

GitHub Actions: Empty Directory Check / Check for Empty_Only-init Directories: fix(streaming): forward tool args on execution-end event

Conclusion: failure

View job details

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 �[36;1m�[0m
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📓 Path-based instructions (4)

**/*.py

📄 CodeRabbit inference engine (Custom checks)

**/*.py: Enforce dependency direction: ui → core → tools → utils/types. Flag violations where core/ imports from ui/, tools/ imports from ui/, tools/ imports from core/, or types/ imports from anything except stdlib/typing
In agent/orchestration code, verify exception handlers clean up state: flag except (UserAbortError, CancelledError) patterns that exist without corresponding cleanup like _remove_dangling_tool_calls() or state rollback. State mutations (messages.append, session modifications) followed by await/function calls that could raise must be cleaned up in except blocks
Check for shallow copy followed by nested dict mutation: flag .copy() on dicts that contain nested dicts/lists. Use deepcopy() instead or use dictionary spreading syntax to avoid mutating original objects
Enforce error handling principle: 'Fail fast, fail loud. No silent fallbacks.' Flag except: pass, except Exception: pass, empty except blocks, catching broad exceptions without re-raising or logging, and returning None/[]/{} sentinel values instead of raising exceptions for invalid inputs

**/*.py: Preserve architectural order rules; do not add new imports across forbidden layers defined in the dependency layer enforcement test
Follow allowed import direction: ui -> core -> tools, with shared-layer imports from utils, types, configuration, constants, exceptions
Prefer existing patterns; mirror command/test naming used in nearby code

Files:

• src/tunacode/core/agents/agent_components/agent_streaming.py

src/tunacode/**/*.py

📄 CodeRabbit inference engine (AGENTS.md)

Do not add TunaCode-owned message-contract wrappers around tinyagent message types; use tinyagent models directly in memory and keep dict payloads at real boundaries

Files:

• src/tunacode/core/agents/agent_components/agent_streaming.py

src/tunacode/**/

📄 CodeRabbit inference engine (AGENTS.md)

Avoid adding empty directories or __init__.py-only directories

Files:

• src/tunacode/core/agents/agent_components/agent_streaming.py

src/tunacode/core/agents/**/*.py

⚙️ CodeRabbit configuration file

src/tunacode/core/agents/**/*.py: CRITICAL REVIEW AREA - Most bugs in last 2 months originated here.

Check for these specific bug patterns:

1. DANGLING TOOL CALLS (PRs #283, #257, #246):

   • Every exception handler in agent loops MUST clean up state
   • If messages are mutated before an await, the except block MUST handle cleanup
   • Look for: except (UserAbortError, asyncio.CancelledError) without cleanup
   • Pattern: _remove_dangling_tool_calls() should be called on abort

2. FROZEN DATACLASS MUTATION (PR #279):

   • Canonical messages are frozen dataclasses
   • NEVER use setattr() on message objects
   • MUST use dataclasses.replace() to create new instances
   • Look for: setattr(message, ...) or message.field = ...

3. SHALLOW COPY CORRUPTION (PR #289):

   • .copy() does NOT deep copy nested dicts
   • Mutating a shallow copy pollutes the original
   • Look for: config.copy() followed by mutation of nested keys
   • Fix: Either use deepcopy() or don't mutate at all

4. GATE 6 - Exception Paths Are First-Class:

   • Every try block: what state is dirty if exception occurs?
   • Every except block: does it restore valid state?
   • Message lists MUST have matching tool calls and returns

Files:

• src/tunacode/core/agents/agent_components/agent_streaming.py

🔇 Additional comments (1)

src/tunacode/core/agents/agent_components/agent_streaming.py (1)

230-236: 🎯 Functional Correctness

Check ToolExecutionEndEvent.args in tiny-agent-os 1.2.28

event_obj.args or {} only works if args is a real attribute on ToolExecutionEndEvent; if this release still omits the field, this line raises AttributeError instead of falling back to {}.

---

📝 Walkthrough

Walkthrough

The _handle_stream_tool_execution_end method now forwards event_obj.args or {} to tool_result_callback instead of always passing an empty dict, allowing actual tool arguments to reach the callback when available.

Changes

Tool Execution Callback Args Fix

Layer / File(s)	Summary
Forward event args to callback src/tunacode/core/agents/agent_components/agent_streaming.py	tool_result_callback now receives event_obj.args or {} instead of a hardcoded empty dict, while tool name/status/result/duration handling is unchanged.

Estimated code review effort: 1 (Trivial) | ~3 minutes

Possibly related issues

• ToolExecutionEndEvent is missing args field (present on Start/Update events) tinyAgent#43: Addresses ToolExecutionEndEvent.args presence at the event source, which this PR's callback change now consumes — flag as a dependency: if the upstream event doesn't reliably populate args, this fix is a no-op or silently passes stale/empty data.
• alchemiststudiosDOTai/tinyAgent#42: Directly tied to the same ToolExecutionEndEvent.args field this change relies on; verify the field's type/default contract matches the event_obj.args or {} fallback logic here to avoid masking upstream bugs (e.g., None vs missing attribute vs empty dict semantics differ).

Note: this is a one-line diff, but the fallback event_obj.args or {} silently swallows falsy-but-valid args (e.g., an empty dict passed intentionally is indistinguishable from None). If CLAUDE.md has a gate on explicit None-checks for event payloads rather than truthy-fallback (common in this codebase's defensive-coding guidance), this should be event_obj.args if event_obj.args is not None else {} instead.

🚥 Pre-merge checks | ✅ 9

✅ Passed checks (9 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title uses a valid fix conventional-commit prefix and accurately describes the streaming tool-args change.
Description check	✅ Passed	The description covers what, why, safety, and dependency, so it is substantially complete despite missing template checklist sections.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Noshallowcopymutation	✅ Passed	No .copy()-then-nested-mutation pattern exists in the touched streaming handler; the PR only forwards event_obj.args or {}.
Exceptionpathcleanup	✅ Passed	PASS: agent_streaming.py cleans up in its CancelledError/Exception handler via _handle_interrupted_stream_cleanup(); this PR only forwards args and doesn’t alter exception paths.
Dependencydirection	✅ Passed	PASS: Gate 2 holds—this core file imports stdlib/tinyagent/core/utils/types only; no ui/ or tools/ imports, and no types/ module changes.
Nosilentfailures	✅ Passed	PASS: The diff only swaps {} for event_obj.args or {}; no added empty excepts, swallowed exceptions, or silent return None paths in the touched handler.

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