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

The description discloses that the operation is a read (GET /projects), is paginated, and supports optional filters. The annotation readOnlyHint=true already indicates safety, and the description adds the pagination behavioral detail, which is useful beyond the annotation.

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 a single, front-loaded sentence covering the core purpose, filters, and pagination, followed by a useful API reference. 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 list endpoint with a readOnlyHint annotation and complete parameter schema, the description adequately covers the tool's purpose and key behaviors (filtering, pagination). It lacks explicit return format details, but the simplicity of listing projects makes it sufficient.

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 provides full descriptions for all five parameters (page, per_page, client_id, is_active, updated_since), so the description need not repeat them. The description's mention of 'active status, client, or updated-since' merely summarizes the schema, adding no new semantic depth. Baseline 3 applies.

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 lists projects, with optional filters for active status, client, and updated-since, and mentions pagination. This distinguishes it from sibling tools like harvest_get_project, which retrieves a single project.

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 provides clear context: use this to list projects with filters and pagination. It does not explicitly exclude alternatives like harvest_get_project, but the 'list' action and filters make the intended use obvious.

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