HTTP 422 · Invalid request

invalid_metadata

Metadata is not valid JSON

HTTP status422

Retry Nonot without a change

FamilyInvalid request

What the API answers

The metadata field is not valid JSON.

The message stays in English, like every API response: branch your script on error.code, which never changes.

What to do

The metadata field was not accepted. Send a valid JSON object, within the limits on size, depth and number of entries.

Invalid request. The request itself was wrong: no file, a type or size that is not accepted, unreadable data, or something that does not exist. Fixed in the script that sends it.

Full response

JSON

{
    "status": "error",
    "error": {
        "code": "invalid_metadata",
        "message": "The metadata field is not valid JSON.",
        "docs": "https://aperture-app.preview.moncompanion.cloud/docs/errors/invalid_metadata"
    },
    "meta": {
        "request_id": "01K2R7M8QF3V9XZ4B6NCDT0YAH",
        "api_version": "v1",
        "duration_ms": 12,
        "timestamp": "2026-10-27T14:32:08+00:00"
    }
}

The meta values are a sample. meta also carries app_version and commit, and a refusal may add error.details with the value at fault.

Codes of the same family

HTTP	Code	What to do	Retry
422	no_file_providedNo file in the request	The request held no file. Send it in the file field of a multipart/form-data body, or as base64 to /api/v1/uploads/base64.	No
415	unsupported_media_typeFile type not accepted	This file type is not accepted. The type is read from the file's content, not from its extension: error.details.detected_mime says what was recognised.	No
413	file_too_largeFile too large	The file exceeds the size allowed for its type. error.details gives the size received and the maximum: shrink the file or compress it before sending.	No
422	invalid_base64Unreadable base64	The base64 payload could not be decoded. Send bare base64, or a complete data URI such as data:image/png;base64,…	No
422	invalid_metadataMetadata is not valid JSON	The metadata field was not accepted. Send a valid JSON object, within the limits on size, depth and number of entries.	No
422	corrupt_uploadUnreadable file	The file could not be read as the type it claims to be: it is truncated or damaged. Send it again in full.	No
404	media_not_foundMedia not found	No media carries this identifier in your organisation, or it was deleted. Check the identifier the upload returned.	No
404	route_not_foundUnknown API path	No route answers this path. Check the URL and the API version against the reference.	No
405	method_not_allowedWrong HTTP method	This route exists, but not with this HTTP method. Use the one the reference gives.	No
404	asset_not_foundAsset not found	No asset carries this key in this category. Check the category and the key, in lowercase.	No
404	asset_version_not_foundAsset version not found	This asset has no version with this number. GET /api/v1/assets/{category}/{key} returns its full version history.	No
404	asset_category_not_foundCategory not found	No asset category carries this slug. Create it first, or check its spelling.	No
409	asset_category_existsCategory already exists	A category already carries this slug. Pick another one, or use the existing category.	No
409	asset_category_not_emptyCategory still holds assets	The category still holds assets. Delete them first: a deleted asset stays in the recycle bin for seven days, where it can still be restored, and keeps the category in use until it is erased. error.details.assets counts the live assets, error.details.trashed_assets those in the bin.	No
422	asset_rule_violatedFile breaks its category's rules	The file breaks a rule of its category. error.details names the rule and the expected value.	No
409	asset_version_currentVersion currently served	This version is the one the asset serves right now. Roll back to another version first, then delete this one.	No
409	asset_version_not_readyVersion not ready	This version is still processing, or its processing failed: it cannot be served. Wait for processing to finish, or pick another version.	No

Every error code