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

Explicitly discloses additive nature, quota consumption, and async behavior beyond the destructiveHint annotation. No contradiction with annotations; provides essential behavioral 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, front-loaded with purpose and key traits (additive, async, polling). No wasted words; every sentence adds value.

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?

Covers async pattern, polling, quota impact, and API endpoint for a tool with moderate complexity. Lacks error handling details but sufficient given no output schema.

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 has 100% coverage, so baseline is 3. Description adds minimal new semantics beyond schema (e.g., mentions 'modifications' are layer overrides). Does not substantially enhance understanding of parameters.

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?

Clearly states 'Generate a video from a video template' with specific verb and resource. Distinguishes from sibling tools like bannerbear_create_image by noting async behavior and polling with bannerbear_get_video.

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?

Provides clear context: additive operation that consumes quota, async with polling. Tells user to poll with bannerbear_get_video for completion. No explicit exclusions but sibling tools suggest alternatives.

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