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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and external-source profile is covered structurally. The description adds only that the source is a 'public' chart returning 'ranked rows' — useful but thin on top of the annotations, with no pagination or result-size context.

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 sentences, zero filler; the core behavior is front-loaded and the sibling routing follows. Every clause earns its place.

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?

With an output schema present, return values need not be described, and read-only/open-world annotations cover the safety profile. Purpose and disambiguation are complete; only marginal behavioral detail (result volume, pagination) is absent.

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 100% and both parameters are documented in the schema with their allowed values. The description only notes that sort and sortDir control ordering, which is already in the schema, so it adds no meaningful semantics beyond the baseline.

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 and resource ('Fetch ranked rows from Box Office Mojo's public franchise chart'), and names the two sibling tools it is not, so the agent can distinguish it from boxofficemojo_franchise and boxofficemojo_brands without opening a schema.

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 routes the agent: use boxofficemojo_franchise for a single franchise's details, boxofficemojo_brands for brand charts. This gives concrete alternative selection context, though it doesn't spell out a when-not condition for the chart itself.

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