diff_crawl

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds behavioral context by noting 'hash-based verdicts from the SQLite history index' and precisely defining the baseline selection rule, which goes beyond the structured annotations.

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 sentences, with the core behavior first and the workflow example last. Each sentence carries distinct information (what, how, when) with no filler or repetition.

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?

Given there is no output schema, the description gives a sufficient high-level contract: added/removed/changed pages with hash-based verdicts. It also reduces ambiguity by naming the exact sequence with crawl_site and get_freshness, so an agent can correctly select and chain the tool; minor gaps like response entry shape remain but are not essential for 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 covers 100% of parameters, so the baseline is 3. The description adds cross-tool value by explaining where `since` comes from ('pass the last_crawl_ended_at value as since'), which is not present in the input schema; the other parameters are already well documented in the schema.

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 clear action and resource: 'Return added/removed/changed pages between the latest crawl and the most recent crawl whose crawl_ended_at <= since.' This is specific enough to distinguish it from sibling tools like get_freshness, and the title 'Diff crawls over time' reinforces the same function.

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?

Provides a concrete workflow: 'Pair with get_freshness: pass the last_crawl_ended_at value as since after running crawl_site with incremental set to true.' This tells an agent when to call it and how to chain it with siblings, though it does not explicitly state exclusions or when-not-to-use alternatives.

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