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

Annotations already indicate read-only and idempotent behavior. The description adds transparency by noting it returns the 'latest stored check', implying no live check is performed. It does not mention potential errors or rate limits, but given the read-only nature and existing annotations, this is acceptable.

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?

The description is concise yet informative, using three sentences to convey purpose, usage, and output. No redundant text; every sentence adds value and the structure flows logically.

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?

Despite lacking an output schema, the description adequately describes what the tool returns: latest stored checks per spec and open issues with fixes. It also implies prioritization ('what to fix first'), giving users a complete picture of what to expect.

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?

The single parameter 'site' is fully described in the schema with examples, and the description reinforces its usage by referencing list_monitored_sites. The meaning is crystal clear with no ambiguity.

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?

The description clearly states the tool's function: retrieving the latest stored checks and open issues for a single monitored site. It also distinguishes from the sibling tool check_site by specifying that this is for already monitored sites, making the purpose unambiguous.

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?

Explicit usage guidance is provided: 'Use this when someone asks what is wrong with a site they monitor, what to fix first, or when it was last checked.' It also directs users to pass the domain or site id from list_monitored_sites, and explicitly says to use check_site for non-monitored sites, leaving no ambiguity about when to use this tool.

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