Fetch App Store screens

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

The description discloses it modifies the brand by saving screens (consistent with readOnlyHint false), is free and keyless, and requires a confident match. It clearly explains failure behavior ('returns 0 and saves nothing') and instructs to relay plainly. This adds significant context beyond the annotations, which already state idempotent and non-destructive.

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 dense and efficient. It front-loads purpose, then gives usage, failure, and success details. Some marketing emphasis (e.g., 'REAL', 'FREE') adds flavor but each sentence contributes value. Slightly verbose in tone, but overall well-structured and not wasteful.

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 only two optional parameters and no output schema, the description fully covers when to use it, what happens on success and failure, and where data is saved. It also mentions that screens are immediately usable. Nothing an agent needs to call it correctly is missing.

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?

Both parameters (appName and brandId) are fully described in the schema (100% coverage). The description minimally repeats appName's default but does not introduce new semantics. Since the schema already carries the parameters' meaning, a 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?

Clearly states it pulls App Store screenshots into the workspace brand, with a specific verb and resource. Mentions the use case (app-ui-tour template) which helps disambiguate from other asset tools. The definition is specific about the source (App Store) and destination (brand).

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?

Explicitly provides conditions for use: when the brand has 0–1 app screens and the user wants make_template_ad(template:'app-ui-tour') or asks to 'pull my app's screenshots'. Also advises against retrying on ambiguous matches, giving both positive and negative guidance. This leaves no ambiguity about when to invoke the tool.

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