openproject-mcp

Get attachment

op_get_attachment

Fetch attachment metadata by ID. Optionally download the file and discover where it is referenced in work package descriptions and comments.

Instructions

Fetch attachment metadata by id. Set saveTo to download the file content to a local path and also return embedLocations showing where the file is referenced in the work package (description and comments).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "id": "<id>"
    },
    "name": "op_get_attachment"
  }
}

Input Schema

Name	Required	Description
`id`	Yes
`raw`	No
`saveTo`	No	Local file path to save the downloaded content to

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0May 26, 2026

TDQS

A4/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses that it's a read operation that can optionally download content, but lacks details on error behavior, permissions, or side effects. Adequate but not comprehensive.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences with no extraneous words. The first sentence states the primary purpose, and the second adds optional functionality. Efficient and well-structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With 3 parameters and no output schema, the description covers the main use cases (fetch metadata, optionally download). It lacks details about return format or error handling but is reasonably complete for a simple fetch tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is low (33%), but the description adds meaning for 'id' (by id) and 'saveTo' (download to local path and return embedLocations). The 'raw' parameter is left unexplained, so it only partially compensates for the schema gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's main action: 'Fetch attachment metadata by id,' using a specific verb and resource. It distinguishes from siblings like op_list_attachments and op_delete_attachment by focusing on a single attachment.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains when to use the tool (to fetch metadata, optionally download content) and mentions the extra embedLocations return when saveTo is set. It does not explicitly exclude scenarios like when not to use it, but the sibling context provides alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.