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

With no annotations, the description carries the full behavioral burden. It does disclose a genuinely useful behavior not present in the schema: the query defaults to '復仇者聯盟：末日崛起' (Avengers: Doomsday). It says nothing about what happens for unknown/ambiguous titles or how the result is presented, so the disclosure is partial.

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?

A single compact sentence, front-loaded with a database scope bracket followed by the function. No wasted words, though the bracketed prefix adds some noise relative to the core statement.

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 simple one-optional-parameter tool with no output schema and no annotations, the description covers the core purpose and the default value. It stops short of explaining the return shape or how ambiguous titles are resolved, leaving gaps an agent would likely hit in practice.

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?

There is a single parameter 'q' with 0% schema description coverage, so the description must compensate. It implicitly identifies the parameter as a work/title query and reveals its default value, but does not state accepted input formats (title, ID, language variants) or matching behavior. Partial compensation for a real coverage gap.

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?

The description names a specific computation (days until a work's theatrical release or premiere) and scopes it to a cinema schedule/release-date database, so the agent knows exactly what it returns. It does not, however, distinguish itself from the close sibling screen__release_calendar, leaving the agent to infer the difference between a single-title countdown and a calendar listing.

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?

There is no explicit when-to-use guidance and no alternatives named, despite screen__release_calendar being an obvious overlapping sibling. The only usage hint is implicit in the word 'countdown', which the agent must interpret on its own.

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