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

Annotations already declare readOnlyHint=false and destructiveHint=false, and the description adds real behavioral context beyond them: it fetches an external sitemap URL, skips already-listed pages (idempotent append), and returns an added count. Minor tension worth noting: fetching a live remote sitemap.xml is arguably external interaction while openWorldHint is false, though it plausibly means the user's own site only.

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 compact sentences: the mechanism and return value first, then the lifecycle guidance. No filler, nothing repeated from the title or schema.

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 single-param mutation with no output schema, it covers the source URL, dedup semantics, return value, and prerequisite ordering. It leaves out failure behavior (missing or malformed sitemap) and whether re-runs are safe, which would round it out.

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?

Only one parameter and schema coverage is 100%, with the schema itself noting projectId comes from list_projects. The description adds no extra meaning about projectId, so the baseline of 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?

States a specific verb chain (read the sitemap at https://<domain>/sitemap.xml) and the resource (pages), plus the dedup scope ('add every page that is not listed yet') and the return value. An agent can distinguish it from list_pages and import_queries without consulting either schema.

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?

Gives explicit timing: run after create_project and again when the site gets new pages. That covers the when-to-use side well, but it does not name an alternative or exclusion (e.g., import_queries for search queries, or what to do if pages already exist manually).

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