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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior. The description adds useful context about the reading contents and the fact that it can be called while a reading is still in progress, though it does not discuss errors or permissions.

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 purpose is front-loaded and the description is short enough to scan. The first sentence is somewhat run-on because it lists several return fields, but it remains useful and does not contain obvious 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 simple one-parameter read tool with annotations and an output schema, the description covers purpose, usage, expected content, and in-progress behavior. The main missing piece is explicit guidance on when to use reading_status instead.

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?

There is only one parameter and schema coverage is 100%, so the schema already fully documents page_id. The description adds that the id comes from read_letter, but this is largely consistent with the schema and does not add much beyond it.

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 that this tool retrieves a page's reading, including transcription, translation, notes, confidence, and link. It distinguishes itself from read_letter by using the page id that read_letter returns, but it does not explicitly differentiate itself from the sibling reading_status tool.

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?

It gives a clear use case: call it with the page id returned by read_letter to show the reading once done or to see whether it is still being read. It does not state when not to use it or explicitly route progress-only checks to reading_status.

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