add_attachment_to_run

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

Annotations already indicate this is a mutating operation (readOnlyHint=false). The description adds crucial behavioral context beyond annotations: the tool is deprecated, and there is a maximum upload size limit. It does not detail all potential side effects, but the annotations and description together offer a solid understanding.

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

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

Two sentences, perfectly front-loaded with the core purpose, followed by deprecation and size limit. Every word earns its place with no redundancy.

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

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

For a simple two-parameter tool with no output schema, the description fully covers what it does, when not to use it (deprecation with alternative), and a critical constraint (size). It is complete for effective tool selection and invocation.

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

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

The input schema already provides full descriptions for both parameters (run_id, file_path), so baseline is 3. The description adds the 256MB upload size constraint, which directly informs the file_path parameter and adds practical meaning beyond the schema.

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

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

The description clearly states the verb 'Add' and the resource 'attachment to a test run' within TestRail. It also distinguishes itself from the sibling 'add_attachment' tool by explicitly marking itself as deprecated and recommending the alternative.

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

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

The description explicitly says 'Deprecated: Prefer add_attachment tool', giving the agent direct guidance to use a different tool instead. It also provides the maximum upload size (256MB), which is a practical constraint for invocation.

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