Blurb Schema Validation

[ycb]

Needs Eng review and prioritization

• Implement comprehensive schema validation for blurbs (e.g., using yamllint, JSON schema, or custom validation logic).
• Ensure all blurbs loaded from blurbs.yaml (and any other sources) are dictionaries with required keys: id, tags, text, etc.
• Add a test to validate blurbs.yaml on every commit/PR.
• Remove or relax the defensive runtime check in select_blurbs once schema validation is in place.
• See PR for temporary defensive fix: https://github.com/ycb/cover-letter-agent/pull/new/qa/07-19-2025

[highvoltag3]

OK, so taking a stab at this, here's my proposed Solution:

• Define a JSON schema for blurbs (required fields, types, constraints).
• Implement a validation utility using jsonschema to check all blurbs files.
• Add a CLI tool and GitHub Action to enforce validation on every commit/PR.
• Expand tests to cover edge cases and malformed blurbs.
• Remove defensive runtime checks once validation is enforced.
• Document the schema and validation process for contributors.

Priority wise I think this is probably something that's not super high on the list, it's more of a QOL improvement.
QWe can sstrt with quick wins like adding basic validation to our existing workflow. Immediate benefits with minimal effort, and we can expand it later.
The schema validation is definitely valuable, but it's more about preventing future problems than some of the other things we have to address. It's the kind of infrastructure improvement that pays dividends over time but isn't blocking current development.

[highvoltag3]

Got excited and decided to just implement this now.. PR