zircote-plugins/cdc-error-plugin (cdc-err)

Design, review, or refactor CLI error messages so they serve BOTH human operators AND LLM agents using the RFC 9457 Problem Details envelope with mandatory agent extensions (retry_after, suggested_fix, code_actions[]). Use whenever the user works on CLI error output, stderr format, exit codes, machine-readable errors, structured error envelopes, dual-format CLI rendering, or reducing token cost of tool_result payloads. Triggers on phrases like "CLI error message", "stderr format", "machine-readable errors", "dual-consumer errors", "problem+json", "RFC 9457 errors", "agent-parseable errors", "review my CLI error messages", "refactor error handling", or when improving error reporting in any CLI (Go, Rust, Python, Node, Ruby, Java, C#, shell). Use this skill even when the user does not cite the RFC or dual-consumer framing — if the work touches CLI error output an agent might parse, this skill applies.

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Source:

github.com/zircote-plugins/cdc-error-plugin

Provenance:

Found by crawling (provenance, not a security rating)

We found this by crawling public sources and nobody has attested to it. That is how most of the registry gets here, and it is not a mark against the artifact — it only means no authenticated act of publication is on record. An artifact can be the vendor's own and still appear here.