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

Annotations already declare readOnly/idempotent/non-destructive/non-openWorld. The description adds value beyond them by stating 'Free' (no credit cost), which annotations do not express, and by detailing the returned content. 'read-only' somewhat repeats readOnlyHint, so not a full 5.

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 tight sentences: the first front-loads what is returned, the second explains how the output is used. No filler or redundant clauses.

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?

An output schema exists and annotations cover the safety profile, so the description needn't explain return values or safety. It is complete enough for a single-parameter read tool, with the only minor gap being no mention of the required projectId.

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 0% and the description never mentions projectId. The phrase 'the project's ... sections' weakly implies a project-scoped input, but the description adds essentially no meaning beyond the self-explanatory parameter name, so it does not compensate for the coverage gap.

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?

States a specific verb ('Returns') and resource ('the project's 30-second storyboard sections') and enumerates the returned fields. It also implicitly distinguishes itself from the section-edit siblings by noting these indexes/IDs are their inputs, so an agent can tell what this tool is for.

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 line 'These indexes and IDs identify inputs to section-edit tools' conveys the workflow context: call this read tool to obtain the indexes/IDs required by the edit tools. It gives clear context but names no explicit alternative tool and states no when-not-to-use condition.

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