provider.chat() had no retry logic — a transient 429 rate limit,
502 gateway error, or network timeout would permanently fail the
entire message. For a system running cron jobs and heartbeats 24/7,
even a brief provider blip causes lost tasks.
Adds _chat_with_retry() that:
- Retries up to 3 times with 1s/2s/4s exponential backoff
- Only retries transient errors (429, 5xx, timeout, connection)
- Returns immediately on permanent errors (400, 401, etc.)
- Falls through to the final attempt if all retries exhaust
ReadFileTool had no file size check — reading a multi-GB file would
load everything into memory and crash the process. Now:
- Rejects files over ~512KB at the byte level (fast stat check)
- Truncates at 128K chars with a notice if content is too long
- Guides the agent to use exec with head/tail/grep for large files
This matches the protection already in ExecTool (10KB) and
WebFetchTool (50KB).
datetime.fromisoformat(at) raises ValueError for malformed strings,
which propagated uncaught and crashed the tool execution. Now catches
ValueError and returns a user-friendly error message instead.
When the LLM returns malformed tool arguments (e.g. a list or string
instead of a dict), validate_params would crash with AttributeError
in _validate() when calling val.items(). Now returns a clear
validation error instead of crashing.
Kiplangatkorir