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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read profile is covered. The description adds that results are image metadata with credited people, but says nothing about pagination, result caps, or how the limit interacts with the filter. With annotations carrying the safety profile, a 3 is appropriate.

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, zero waste, with the resource/return shape front-loaded and the filtering guidance trailing. Nothing redundant.

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 the return values need no prose explanation, and the read-only safety is covered by annotations. The remaining gap is the unexplained id/url/limit parameters, which matters because an agent must decide how to identify the title and bound results.

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% across four parameters, so the description must carry the load. It explains only the `type` filter and its value source; `id`, `url`, and `limit` are left entirely unexplained, including whether id or url is the primary selector. Partial compensation, not full.

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 ('IMDb title media index') and enumerates the returned fields (image URL, dimensions, caption, credited people), which lets an agent separate it from the sibling imdb_name_images (name-based) 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?

Gives concrete invocation guidance: 'Filter with type; call imdb_image_types for the accepted values.' That routes the agent to the right helper for enum discovery. It does not, however, say when to prefer this over sibling media tools such as imdb_title_videos or imdb_name_images.

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