error-message-manager

error-message-manager

Rewrite vague, delayed, or low-context Julia error messages into structured, actionable diagnostics. The goal is errors that tell the user exactly what went wrong, what was expected, what was received, and—whenever a likely fix exists— what to do next. Prefer catching mistakes early (at API boundaries) over letting them propagate into cryptic numerical failures.

Workflow

Step 0 — Offer an Explore agent for multi-file scope

If the user's request covers more than one file — a whole directory, a module, or the entire repo — offer to spawn an Explore agent before doing any file reads yourself. The agent runs all the reads in parallel without flooding the main context, and returns a structured inventory you can act on directly.

When to offer: any time the target is a directory path (e.g. src/) or a vague scope like "the whole package" or "all the source files".

Offer text (adapt as needed):

"This spans multiple files — I'd recommend spawning an Explore agent to survey all throw/@assert/error sites in parallel. It keeps the audit fast and leaves the main context clean for the actual rewrites. Want me to do that?"

Agent prompt to use (fill in <path> and <package_name>):

Audit `<path>` for error-raising patterns. For every `@assert`, `error(`, or
`throw(` site in every `.jl` file:

1. Record: file, line number, exception type (or "bare @assert" / "bare error"),
   and the full message text (including multiline strings).
2. Classify message quality:
   - "good"  — has `$(expr)` interpolation showing the actual received value, and
     is either short (≤3 lines) or already in a `_throw_` helper function
   - "long-inline" — message content is good, but the body exceeds 3 lines and
     the throw is written inline (not in a `_throw_` helper)
   - "vague" — missing a received value, or no Expected/Got structure
   - "missing" — bare `@assert` with no message at all
3. Note whether the site is at an API boundary (user-facing input) or an internal
   invariant (would require a package bug to fire).

Return a markdown table with columns:
  File | Line | Exception type | Quality | Notes (one-line note on what's wrong if vague/missing/long-inline)

Focus only on sites that are "vague", "missing", or "long-inline" — skip "good" ones.