Skip to content

Failed to read a supporting file

Type URI: https://modeled-information-format.github.io/mif-rs/references/errors/mif-rh-io/v1 HTTP status: 500 by default, but dynamically reclassified — see below Exit code: 1 Emitted by: mif-rh (MifRhError::Io)

failed to read {path}: {source}

A file read failed at the OS level while reading a supporting file — an ontology directory, a map file, or harness.config.json. mif-cli, mif-mcp, and mif-ontology each report the identical conceptual failure through their own mif-cli-io/mif-mcp-io/mif-ontology-io problem types instead of this one — each crate’s Io-shaped variant maps to its own distinct, versioned slug, not a slug shared across crates.

Status is not fixed. mif_problem::classify_io_error inspects the underlying std::io::ErrorKind and overrides the status at emission time:

ErrorKind Status Applicability
NotFound 404 MaybeIncorrect — verify the path exists
PermissionDenied 403 MaybeIncorrect — verify permissions
anything else 500 Unspecified — genuine I/O fault, not a path mistake

Depends on the classified status (see table above) — always MaybeIncorrect for 404/403, Unspecified for a genuine I/O fault at 500.