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

Annotations already declare readOnlyHint=true, openWorldHint=true, destructiveHint=false, so safety is covered. The description adds genuinely new behavior beyond that: the call returns progress plus exactly one page of results, and the response carries a nextOffset sentinel (null = no more pages), which the agent needs to drive pagination.

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 sentences, no filler. The core capability (progress + one page) comes first, and the pagination instruction that governs repeated invocation follows it.

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 the return-value burden and does explain the shape (progress, one page, nextOffset sentinel). It is nearly sufficient; the truncation signal (data.truncated) and terminal-condition wording are left to the schema, which is acceptable but not ideal given no output schema.

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 coverage is 100%, so baseline would be 3, but the description adds a cross-call relationship the schema cannot express: the value to pass as offset comes from the previous call's nextOffset. Offset/limit/maxCharsPerPage mechanics are otherwise left to 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 specific verb+resource ('Read a crawl') and ties the resource to its producer ('started with crawl'), so the agent can distinguish this status/read tool from the crawl starter. It does not explicitly contrast with the parallel batch_status sibling, leaving that differentiation to be inferred.

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 a clear precondition (a crawl started with crawl) and an actionable loop rule for following pages via nextOffset→offset. It never states when NOT to use it or when batch_status is the right alternative, so it stops short of full alternative-routing.

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