Review a pending send

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint. The description adds useful behavioral context by explicitly stating it is read-only and by explaining that approval is not performed here but requires a separate review page. This goes beyond the annotations and clarifies a key operational boundary.

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 two sentences long, begins with the primary purpose, and every clause earns its place. It packs the key use case, the read-only nature, and the important limitation about approval without any filler.

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 single-parameter, read-only tool with strong annotations, the description is complete. It tells the agent what will be retrieved (full contents including body), what not to expect (approval capability), and where to direct the user for approval. No output schema is present, but the description sufficiently clarifies the return intent.

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 schema already covers the single parameter approval_id at 100%, including its type, format, and source context. The description does not add new parameter semantics beyond what the schema provides, so the baseline score of 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 ('Fetch'), a specific resource (a send waiting for human approval), and the purpose (display in the review card). It clearly distinguishes itself from approval_decide by noting that approving is not possible here.

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: for a send pending approval, to show in the review card. It also gives a clear exclusion: approving is not possible from this tool and requires the signed-in review page linked as review_url. This helps an agent avoid choosing the wrong sibling.

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