Inspect

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

The annotations already declare readOnlyHint and openWorldHint, and the description adds meaningful behavior beyond that: the operation never mutates the document, frame starts at 1, and out-of-range frames are clamped by the Lua side. This gives the agent concrete expectations about side effects and edge-case handling.

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 short sentences deliver the purpose, safety characteristic, and frame-handling detail with no redundancy. The key purpose is front-loaded, and every clause contributes useful information.

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?

The tool is simple and the description covers the core use case, safety, and frame behavior. It is incomplete on parameter semantics for session_id, view, and scale, and it does not explain what the returned preview/metrics look like, which matters because there is 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?

With 0% schema description coverage, the description must compensate, but it only explains frame semantics (1-based, clamped). The required session_id and the view and scale parameters are left undefined, so the agent must guess their meaning or defaults.

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 action and output: it returns a canvas preview and quantitative metrics. The explicit 'read-only, never modifies the document' note clearly sets it apart from the modification-oriented siblings apply_operations and run_lua.

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 provides useful context for animated documents by explaining how to use frame and that out-of-bounds values are clamped. However, it never explicitly tells an agent when to choose inspect over apply_operations or run_lua; the read-only statement only implies the appropriate use case.

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