fix(browser): guard module-level int() against non-numeric env var

[annguyenNous]

Fix: Guard module-level int() against non-numeric env var

File: tools/browser_tool.py, line 1181

Bug: BROWSER_SESSION_INACTIVITY_TIMEOUT is cast via int() at module level without any error handling. If a user sets BROWSER_INACTIVITY_TIMEOUT to a non-numeric string (e.g. "abc" or an empty string), the entire browser_tool module fails to import with an unhandled ValueError, breaking all browser functionality.

Fix: Wrap the module-level int() call in try/except (ValueError, TypeError) with a fallback to the default value of 300 seconds. This matches the defensive pattern used elsewhere in the codebase (e.g. _env_float() helper in chat_completion_helpers.py).

Impact: High — any misconfigured env var currently causes a complete browser tool outage with no recovery path.

[alt-glitch]

Same class of fix as #35790 (env var cast guards). This PR covers browser_tool.py while #35790 covers chat_completion_helpers.py and platform adapter files. Related to #14756 (merged, web_server float guard).

[tonydwb]

Code Review Summary

Verdict: Approved ✅

🔍 What this does

Wraps the module-level int(os.environ.get(...)) call in a try/except (ValueError, TypeError) so a non-numeric BROWSER_INACTIVITY_TIMEOUT env var doesn't crash the entire browser_tool module at import time.

✅ Looks Good

• Correctness: Falls back to the documented default (300s) on any parsing failure — matches the existing _env_float() defensive pattern in chat_completion_helpers.py.
• Edge cases: Handles both ValueError (non-numeric string like "abc") and TypeError (e.g. None from os.environ.get with no default — though the default is provided here, the except TypeError is a good belt-and-suspenders guard).
• Impact: Prevents a silent full-outage of browser tooling due to misconfiguration.

💡 Suggestion (non-blocking)

Consider extracting this pattern into a reusable helper like _env_int(name, default) to match _env_float() and apply consistently across the codebase. Not needed in this PR — can be a follow-up refactor.

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Reviewed by Hermes Agent (cron)

[teknium1]

Thanks for identifying this import-time failure mode. This is an automated hermes-sweeper review; the requested guarantee is already present on current main.

• Commit 2912d943705058cc55f7f5fc102c99dbb1efcc27 (fix: guard int(os.getenv()) casts against malformed env vars (#40598)) replaced this exact browser timeout cast with env_int(...); it also credits @annguyenNous as co-author.
• Current tools/browser_tool.py:1421 resolves BROWSER_INACTIVITY_TIMEOUT via env_int, and utils.py:410-418 returns the provided default for empty, non-numeric, or otherwise invalid integer input.
• The later timeout-resolution refactor at tools/browser_tool.py:1420-1433 preserves that safe environment fallback while making config.yaml authoritative.

Closing as implemented on main.