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

Annotations already provide strong safety signals (readOnlyHint, idempotentHint, destructiveHint=false). The description adds the specific metadata fields returned and the intended use case, but does not disclose additional behavioral traits such as authentication, rate limits, or potential side effects. The field list may be redundant given the output schema exists.

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 two sentences, front-loaded with the action and key fields, followed by a concise usage guideline. No wasted words.

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 one-parameter, read-only metadata fetcher with an output schema and strong annotations, the description fully covers purpose, usage, and field content. It is complete without being verbose.

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?

Schema description coverage is 100%. The project_id parameter is well-described with where to obtain it (project URL or prior list_scenarios call). The tool description adds no additional parameter semantics, so baseline 3 is appropriate.

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 'fetch' and the specific resource 'PhaseFolio project's metadata', followed by an explicit list of fields. It distinguishes this tool from siblings like get_scenario by focusing on project metadata and clinical context.

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 states when to use it: 'when you need to ground an analysis question in the project's clinical context before fetching scenarios.' This implies a sequencing with scenario tools, though it does not name alternative tools or explicitly state when not to use it.

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