Files
hermes-agent/agent/turn_tool_validation.py

249 lines
11 KiB
Python

"""Tool-call validation for the conversation turn loop: unknown tool names (with
auto-repair and the 3-strike partial exit) and malformed JSON arguments (retry, then
recovery tool results).
Extracted from ``run_conversation``. Role alternation is preserved on every path: an
invalid batch is answered with tool-role error results (never a user message), and
the exits close any open tool-result tail (#48879). Nothing here imports
``agent.conversation_loop`` at module level (cycle); loop-internal helpers resolve lazily.
"""
from __future__ import annotations
import json
import logging
from dataclasses import dataclass
from typing import Any, Dict, List, Optional
from agent.message_metadata import append_message
from agent.message_sanitization import close_interrupted_tool_sequence, coalesce_tool_call_id
logger = logging.getLogger("agent.conversation_loop")
@dataclass
class ToolValidationVerdict:
"""Outcome of ``validate_tool_calls``.
``action``: ``"ok"`` (dispatch the calls), ``"continue"`` (re-issue the API call —
error results / retry state were recorded) or ``"return"`` (terminal partial
result in ``result``). ``mixed_invalid_batch`` is True when the batch contains BOTH
valid and unknown tool names: only the invalid calls get error results, the valid
ones run."""
action: str
result: Optional[Dict[str, Any]]
mixed_invalid_batch: bool
def validate_tool_calls(
agent: Any,
assistant_message: Any,
finish_reason: str,
*,
messages: List[Dict[str, Any]],
conversation_history: Any,
api_call_count: int,
effective_task_id: Any,
) -> ToolValidationVerdict:
"""Validate ``assistant_message.tool_calls`` in place (ids uniquified, names
repaired, dict/empty args normalized to JSON strings). Strikes for invalid names
advance only when a turn has NO valid call, so a degenerate model still halts at
3; args cut off mid-stream (routers rewrite ``length`` → ``tool_calls``) are refused
outright rather than retried."""
from agent.conversation_loop import _invalid_tool_name_error_content
_mixed_invalid_batch = False
def _verdict(action: str, result: Optional[Dict[str, Any]] = None) -> ToolValidationVerdict:
return ToolValidationVerdict(action=action, result=result, mixed_invalid_batch=_mixed_invalid_batch)
# Uniquify duplicate tool-call ids BEFORE any downstream consumer: the
# pre-API sanitizer keeps only the first call/result per id. See
# _uniquify_tool_call_ids.
agent._uniquify_tool_call_ids(assistant_message.tool_calls)
# Validate tool call names - detect model hallucinations
# Repair mismatched tool names before validating
for tc in assistant_message.tool_calls:
if tc.function.name not in agent.valid_tool_names:
repaired = agent._repair_tool_call(tc.function.name)
if repaired:
print(f"{agent.log_prefix}🔧 Auto-repaired tool name: '{tc.function.name}' -> '{repaired}'")
tc.function.name = repaired
invalid_tool_calls = [
tc.function.name for tc in assistant_message.tool_calls
if tc.function.name not in agent.valid_tool_names
]
# Mixed batch: error-result ONLY the invalid calls and run the valid
# ones; voiding the turn discards real work. Strikes advance only when a
# turn has NO valid call, so a degenerate model still halts at 3.
_mixed_invalid_batch = bool(invalid_tool_calls) and any(
tc.function.name in agent.valid_tool_names
for tc in assistant_message.tool_calls
)
if _mixed_invalid_batch:
agent._invalid_tool_retries = 0
invalid_name = invalid_tool_calls[0]
invalid_preview = invalid_name[:80] + "..." if len(invalid_name) > 80 else invalid_name
_n_valid = sum(
1 for tc in assistant_message.tool_calls
if tc.function.name in agent.valid_tool_names
)
agent._buffer_vprint(
f"⚠️ Unknown tool '{invalid_preview}' in batch — erroring that call, "
f"executing {_n_valid} valid call(s)"
)
elif invalid_tool_calls:
# Track retries for invalid tool calls
agent._invalid_tool_retries += 1
# Return helpful error to model — model can agent-correct next turn
invalid_name = invalid_tool_calls[0]
invalid_preview = invalid_name[:80] + "..." if len(invalid_name) > 80 else invalid_name
agent._buffer_vprint(f"⚠️ Unknown tool '{invalid_preview}' — sending error to model for agent-correction ({agent._invalid_tool_retries}/3)")
if agent._invalid_tool_retries >= 3:
agent._flush_status_buffer()
agent._vprint(f"{agent.log_prefix}❌ Max retries (3) for invalid tool calls exceeded. Stopping as partial.", force=True)
agent._invalid_tool_retries = 0
_final_response = f"Model generated invalid tool call: {invalid_preview}"
# Prior retries or an earlier tool batch leave a tool-result
# tail; close it as interrupt aborts do so the next turn is not
# tool→user. (#48879)
close_interrupted_tool_sequence(messages, _final_response)
agent._persist_session(messages, conversation_history)
return _verdict("return", {
"final_response": _final_response,
"messages": messages,
"api_calls": api_call_count,
"completed": False,
"partial": True,
"error": _final_response
})
assistant_msg = agent._build_assistant_message(assistant_message, finish_reason)
append_message(messages, assistant_msg)
for tc in assistant_message.tool_calls:
_tc_name = tc.function.name
if _tc_name not in agent.valid_tool_names:
# See _invalid_tool_name_error_content for the
# blank-name anti-priming rationale (#47967).
content = _invalid_tool_name_error_content(
_tc_name, agent.valid_tool_names
)
else:
content = "Skipped: another tool call in this turn used an invalid name. Please retry this tool call."
append_message(messages, {
"role": "tool",
"name": tc.function.name,
"tool_call_id": coalesce_tool_call_id(tc),
"content": content,
})
return _verdict("continue")
# Reset retry counter on successful tool call validation
agent._invalid_tool_retries = 0
# Validate tool call arguments are valid JSON
# Handle empty strings as empty objects (common model quirk)
invalid_json_args = []
for tc in assistant_message.tool_calls:
args = tc.function.arguments
if isinstance(args, (dict, list)):
tc.function.arguments = json.dumps(args)
continue
if args is not None and not isinstance(args, str):
tc.function.arguments = str(args)
args = tc.function.arguments
# Treat empty/whitespace strings as empty object
if not args or not args.strip():
tc.function.arguments = "{}"
continue
try:
json.loads(args)
except json.JSONDecodeError as e:
if (
_mixed_invalid_batch
and tc.function.name not in agent.valid_tool_names
):
# This call never executes (invalid-name error result
# below); don't let its broken args trigger the whole-turn
# JSON retry.
continue
invalid_json_args.append((tc.function.name, str(e)))
if invalid_json_args:
# Routers may rewrite finish_reason "length" → "tool_calls", hiding
# truncation; args not ending in } or ] (stripped) were cut off
# mid-stream.
_truncated = any(
not (tc.function.arguments or "").rstrip().endswith(("}", "]"))
for tc in assistant_message.tool_calls
if tc.function.name in {n for n, _ in invalid_json_args}
)
if _truncated:
agent._vprint(
f"{agent.log_prefix}⚠️ Truncated tool call arguments detected "
f"(finish_reason={finish_reason!r}) — refusing to execute.",
force=True,
)
agent._invalid_json_retries = 0
agent._cleanup_task_resources(effective_task_id)
_final_response = "Response truncated due to output length limit"
# Same tool-tail close as interrupt / invalid-tool
# exhaustion — this path never reaches finalize_turn.
close_interrupted_tool_sequence(messages, _final_response)
agent._persist_session(messages, conversation_history)
return _verdict("return", {
"final_response": _final_response,
"messages": messages,
"api_calls": api_call_count,
"completed": False,
"partial": True,
"error": _final_response,
})
# Track retries for invalid JSON arguments
agent._invalid_json_retries += 1
tool_name, error_msg = invalid_json_args[0]
agent._buffer_vprint(f"⚠️ Invalid JSON in tool call arguments for '{tool_name}': {error_msg}")
if agent._invalid_json_retries < 3:
agent._buffer_vprint(f"🔄 Retrying API call ({agent._invalid_json_retries}/3)...")
# Don't add anything to messages, just retry the API call
return _verdict("continue")
else:
# Instead of returning partial, inject tool error results so the model can recover.
# Using tool results (not user messages) preserves role alternation.
agent._buffer_vprint("⚠️ Injecting recovery tool results for invalid JSON...")
agent._invalid_json_retries = 0 # Reset for next attempt
# Append the assistant message with its (broken) tool_calls
recovery_assistant = agent._build_assistant_message(assistant_message, finish_reason)
append_message(messages, recovery_assistant)
# Respond with tool error results for each tool call
invalid_names = {name for name, _ in invalid_json_args}
for tc in assistant_message.tool_calls:
if tc.function.name in invalid_names:
err = next(e for n, e in invalid_json_args if n == tc.function.name)
tool_result = (
f"Error: Invalid JSON arguments. {err}. "
f"For tools with no required parameters, use an empty object: {{}}. "
f"Please retry with valid JSON."
)
else:
tool_result = "Skipped: other tool call in this response had invalid JSON."
append_message(messages, {
"role": "tool",
"name": tc.function.name,
"tool_call_id": coalesce_tool_call_id(tc),
"content": tool_result,
})
return _verdict("continue")
# Reset retry counter on successful JSON validation
agent._invalid_json_retries = 0
return _verdict("ok")