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

Annotations already declare read-only, idempotent, non-destructive, closed-world, so the safety bar is low. The description still adds real behavioral context beyond them: a 50-item page cap, the nextCursor follow-up loop, and the fact that `include` loads the parent project chain. It does not describe failure or auth behavior, keeping it out of 5 territory.

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?

Three short sentences, zero filler, with the core purpose front-loaded before pagination and the optional include parameter. Every sentence carries information an agent needs to call the tool.

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?

With no output schema, the description carries return-value burden and does so partially: it names the returned entity (cited sources) and ordering (by domain) plus pagination. An agent knows what comes back and how to page, though richer result-shape detail is absent.

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%, so all three parameters (cursor, include, project_id) are already documented in the schema — baseline is 3. The description reinforces nextCursor and include but adds no syntax or meaning the schema lacks.

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?

States a specific verb ('List') and resource ('sources cited by AI platforms when responding to a project's prompts') with an explicit ordering ('by domain'). Clear on its own, but does not distinguish itself from close siblings like list-citations-tool or list-source-analytics-tool, so it stops short of a 5.

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?

Usage is implied by the scope phrase ('sources cited by AI platforms when responding to a project's prompts') and the optional `include` for the parent project chain, but there is no explicit when-to-use/when-not guidance and no naming of alternatives in a sibling set dense with other list-* source tools.

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