add_attachment

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

Annotations already indicate a non-read-only, non-destructive mutation. The description adds valuable behavioral context: directories are automatically zipped and there is a 256MB upload limit. These details go beyond the annotation hints and help the agent anticipate side effects.

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?

The description is three concise sentences, front-loaded with the primary purpose and followed by two relevant operational details. Every sentence earns its place, with no filler or 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?

The description covers the core action and significant behavioral constraints (zip, size), but it lacks return-value expectations or prerequisites like requiring the entity to exist. With no output schema, the description carries the burden of explaining outcomes, and it is silent on what the caller should expect on success.

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 covers all three parameters with descriptions (100% coverage), so the baseline is 3. The description adds context for file_path (directory zipping) but does not introduce new meaning for entity_type or entity_id beyond the schema's existing descriptions.

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 tool's action: 'Add an attachment to a test case or test run in TestRail.' It specifies the verb and resource, making the core function obvious. However, it does not differentiate from the sibling tool add_attachment_to_run, which likely serves a similar purpose for runs, creating potential ambiguity.

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?

No guidance is provided on when to choose this tool over alternatives like add_attachment_to_run. The description mentions behavioral details (directory zipping, size limit) but does not state exclusions, prerequisites, or scenarios where another tool would be more appropriate.

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