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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false. The description adds meaningful behavioral context: the URL is 'signed, expiring', and the return shape is `{ url, viewToken, expiresAt }`. It also clarifies that this is a non-destructive, open-world operation (issuing a link) without contradicting annotations. It doesn't mention rate limits or revocation, but the core behavior is well disclosed.

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, zero waste. The core action and mechanism are front-loaded, the use case is stated, and the return shape is given. Every sentence earns its place.

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 tool with 4 params, no output schema, and moderate annotation coverage, the description is quite complete: it states the action, the use case, the mechanism, and the return shape. The only gaps are the semantics of sessionToken and expiresSeconds, which are partially inferable from the schema. Given the tool's complexity, this is strong but not perfect.

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 50%, so the schema documents hatchId and tenantId but not sessionToken or expiresSeconds. The description adds the return shape and the `?vt=…` mechanism, but it doesn't explain the semantics of sessionToken or expiresSeconds beyond what the schema's min/max implies. The description partially compensates for the coverage gap but not fully, so a 3 is appropriate.

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 states a specific verb ('issue'), a specific resource ('guest view URL'), and a distinguishing mechanism ('signed, expiring', '?vt=…'). It also clarifies the intended use case ('private run reports without forever-tier password auth'), which differentiates it from sibling tools like auth or lookup. The title 'Guest view link' is reinforced, not merely restated.

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?

The description explicitly says when to use it: 'Use for private run reports without forever-tier password auth.' This gives clear context. It doesn't explicitly name alternatives or exclusions, but the sibling list and the phrase 'without forever-tier password auth' imply the alternative (auth) and the condition. A 4 is appropriate because the guidance is clear but not exhaustive.

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