Error Codes

All errors are returned as JSON on stderr with a consistent structure:


{
  "ok": false,
  "error": {
    "code": "ERROR_CODE",
    "message": "Human-readable description",
    "details": { ... }
  }
}

Error Code Reference

Code	Description
`PROJECT_NOT_FOUND`	No `.mdp/` directory found
`ISSUE_NOT_FOUND`	Issue ID does not exist
`MILESTONE_NOT_FOUND`	Milestone ID does not exist
`TEMPLATE_NOT_FOUND`	Template file not found
`INVALID_STATUS`	Status name not in config
`INVALID_PRIORITY`	Priority name not in config
`INVALID_TYPE`	Type name not in config
`INVALID_LABEL`	Label name not in config
`INVALID_DATE`	Date string cannot be parsed
`INVALID_ID`	Referenced ID (blockedBy, parent, etc.) does not exist
`MISSING_REQUIRED`	Required flag is missing
`ALREADY_EXISTS`	`.mdp/` already exists (on `init` without `--force`)
`CIRCULAR_DEPENDENCY`	`blockedBy` or `parent` change would create a cycle
`WRITE_ERROR`	Filesystem write failed
`PARSE_ERROR`	Markdown/YAML parsing failed
`INVALID_INPUT`	Invalid JSON input or missing required fields (used by `batch-create`, `batch-update`)
`CONFIG_ERROR`	project.json is missing or invalid

Example Errors

Invalid Status


mdp issue update --id ISS-1 --status "bogus"


{
  "ok": false,
  "error": {
    "code": "INVALID_STATUS",
    "message": "Invalid status \"bogus\"",
    "details": {}
  }
}

Issue Not Found


mdp issue get --id ISS-999


{
  "ok": false,
  "error": {
    "code": "ISSUE_NOT_FOUND",
    "message": "Issue ISS-999 not found",
    "details": { "id": "ISS-999" }
  }
}

Invalid Label


mdp issue create -t "Test" -l "nonexistent"


{
  "ok": false,
  "error": {
    "code": "INVALID_LABEL",
    "message": "Invalid label \"nonexistent\"",
    "details": {}
  }
}

Circular Dependency

When ISS-2 already has blockedBy: [ISS-1]:


mdp issue update --id ISS-1 --add-blocked-by ISS-2


{
  "ok": false,
  "error": {
    "code": "CIRCULAR_DEPENDENCY",
    "message": "Adding ISS-2 to blockedBy of ISS-1 would create a circular dependency",
    "details": {}
  }
}

Exit Codes

Code	Meaning
`0`	Success
`1`	General error
`2`	Project not found

Warnings

Non-fatal issues are included in the warnings array of successful responses. For example, a command may succeed but include warnings about deprecated usage or other non-critical issues.