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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuine context beyond them: the data comes from a credential-free public IMDb page (no auth required) and is 'normalized'. It stops short of describing pagination or freshness, so a 4 rather than 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?

Three tight sentences, front-loaded with purpose, then the invocation constraint, then the alternative tool. No filler and every sentence carries information.

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 annotations cover the safety profile. The description covers purpose, invocation, and the search alternative. It leaves unstated how this differs from the numerous other imdb_title_* detail tools, a minor gap.

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 coverage is 100%, so baseline is 3, but the description adds a real constraint the schema does not encode: exactly one of id or url must be supplied (mutual exclusion). This is meaningful semantic value beyond the per-parameter descriptions.

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 ('Returns normalized IMDb title metadata') and scopes the source ('credential-free public IMDb title page'). It also names the sibling imdb_search_title as the alternative, letting an agent distinguish lookup from search without opening schemas.

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 explicit invocation guidance ('Pass exactly one of id or url') and routes search use cases to imdb_search_title. However, it does not clarify when to use this versus the many other imdb_title_* siblings (credits, awards, ratings, etc.), so the alternative mapping is only partial.

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