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

Adds substantive behavior beyond the annotations: indexing happens in the background, sitemap is tried first with same-host links as fallback, and the index is kept current. Annotations already cover the safety profile (non-read-only, non-idempotent, non-destructive), and the description usefully supplements them rather than contradicting them.

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 short paragraphs, front-loaded with the action and its effect, then the scoping hint and progress-check pointer. No filler sentences, though the second paragraph could be folded more tightly.

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 mutation tool with no output schema, the description covers what happens after the call (background indexing), how to vary scope, and where to monitor progress. It omits error/duplicate handling and expected timing, but is otherwise adequate for correct invocation.

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 both required and optional parameters are already documented, including `path_prefix` and `refresh_interval`. The description largely restates the path_prefix semantics already in the schema and adds no format or boundary detail beyond it, so 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?

States a specific verb and resource ('Add a website to a knowledge collection') and explains the indexing consequence, which distinguishes it from collections_add_file and collections_remove_website nearby. It does not, however, explicitly contrast itself with sibling tools such as collections_refresh_website.

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 clear operational context: use `path_prefix` to scope indexing to one section, and check progress with collections.list_websites. It lacks any explicit when-not-to-use guidance, such as what to do if the site is already added.

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