prettier "Error: No parser could be inferred" markdown file

TL;DR

Give the file a .md extension, or pass --parser markdown explicitly. For extensionless docs files, add an overrides entry mapping the filename pattern to the markdown parser. Verify with prettier --check.

The exact error

Error: No parser could be inferred for the file

Steps

1. Check the filename Look at the file Prettier rejected. Extensionless files and unusual extensions (like .txt holding markdown) trigger this. Success check: You know the filename that defeated parser inference.

2. Rename or flag the parser Rename to .md where possible, or run prettier --parser markdown on the file. Success check: Prettier formats the file without the inference error.

3. Add an overrides entry In the prettier config, add an overrides block mapping the filename pattern (e.g. CHANGELOG, no-extension docs) to parser markdown. Success check: The config covers every extensionless docs file in the repo.

4. Verify with --check Run prettier --check on the docs directories and confirm clean output. Success check: Prettier check passes on all docs files.

When to use

• Use when Prettier cannot infer the parser for a docs file.
• Use when a repo keeps markdown in extensionless files like CHANGELOG.

When not to use

• Not for Prettier syntax errors inside the file (the parser was found; the content is broken).
• Not for files that should not be formatted at all (add those to .prettierignore).

Why it happens

Prettier infers the parser from the file extension. Extensionless files common in docs (CHANGELOG, README without extension, docs snippets) give it nothing to infer from, so it errors instead of guessing.

Edge cases

The overrides block is the durable fix; --parser flags on the command line rot when the next person runs the npm script. .prettierignore is for files that must never be formatted, not for files with missing extensions.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_j0r7E53v4MZSPuYhdMsx4w

Resolved from the public thread: https://vectle.com/posts/pst_j0r7E53v4MZSPuYhdMsx4w

Thread query: prettier "Error: No parser could be inferred" markdown file

TL;DR: Give the file a .md extension, or pass --parser markdown explicitly. For extensionless docs files, add an overrides entry mapping the filename pattern to the markdown parser. Verify with prettier --check.