fix github label validation and error handling

[zzstoatzz]

summary

• fix pydantic validation error when github returns null label descriptions
• remove ERROR_HANDLED completed state so flows properly fail

changes

github labels fix

• GitHubLabel.description now accepts str | None
• github api sometimes returns null for label descriptions
• fixes validation error: Input should be a valid string [type=string_type, input_value=None]

error handling fix

• removed Completed(name="ERROR_HANDLED") pattern
• errors are now re-raised after sending user-friendly slack message
• maintains good UX while allowing proper flow failure monitoring

why

proper failure states are important for:

• alerting/monitoring
• understanding when the bot actually fails vs succeeds
• debugging issues in production

🤖 Generated with Claude Code

[Copilot]

Pull Request Overview

This PR ensures the Slackbot handles GitHub’s nullable label descriptions and improves error handling to allow flows to properly fail for monitoring.

• Allow GitHub label descriptions to be None to prevent Pydantic validation errors.
• Replace swallowing errors with a direct re-raise after notifying the user, removing the ERROR_HANDLED Completed state.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
examples/slackbot/src/slackbot/github/models.py	Model change: description now allows None to handle GitHub’s null label descriptions.
examples/slackbot/src/slackbot/api.py	Error handling updated to re-raise exceptions rather than returning a Completed(ERROR_HANDLED).

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[Copilot]

[nitpick] The field type allows None but the default remains an empty string. This mixes two different sentinel values for 'no description' and can confuse downstream consumers; consider setting the default to None to align with the Optional type.

Suggested change

	description: str | None = Field(default="")
	description: str | None = Field(default=None)

[Copilot]

Because mark_thread_completed is in a finally block, it will run even when an exception is re-raised, marking the thread as completed on failure. If the intent is to signal a failed flow, move this call to the success path (outside finally) or add a separate failure path (e.g., mark_thread_failed) for the except branch.