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

Annotations only cover readOnlyHint/openWorldHint, so the description adds real value by disclosing the empty-result behavior: a valid title without box office data returns has_box_office false instead of raising an error. That is exactly the kind of edge-case contract an agent needs. It does not discuss rate limits or partial data, so not a 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 sentences, zero filler, with the payload description front-loaded and the edge-case behavior appended. 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?

An output schema exists, so field-level return documentation is unnecessary, and the description covers scope plus the false-flag failure mode. The only gap is that both parameters are optional with no hint about which to supply (id vs url), which an agent would have to infer.

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 (id, url) are fully documented in the schema at 100% coverage, so baseline 3 applies. The description adds no syntax, format, or id/url precedence guidance beyond what the schema already states.

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?

Names a specific resource and verb ('IMDb title box office summary') and enumerates exactly what it returns: lifetime gross by market, domestic opening weekend, production budget. That content list separates it from siblings like imdb_title_ratings or imdb_title_awards. It stops short of explicitly naming the sibling an agent should use for non-box-office metadata, so a 4 rather than 5.

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?

Usage is implied by the description's scope — fetch financial data for a specific IMDb title — but there is no explicit when-to-use/when-not statement and no alternative named from the large imdb_* family (e.g., use imdb_title for general details). Adequate but inferential.

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