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

The description adds useful behavioral context beyond annotations: the tool returns export and job IDs and can be polled via exports_list, implying an asynchronous operation. Annotations already indicate it is not read-only or idempotent, and the description does not contradict them. It could mention side effects (e.g., rendering costs or project state changes), but the polling hint covers the main follow-up behavior.

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. The first states exactly what the tool does; the second explains the return value and the follow-up polling mechanism. No wasted words, and the most important information is front-loaded.

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?

The tool has 5 parameters, an output schema, and is a side-effecting operation. The description covers the key flow (start export, get IDs, poll with exports_list) and leverages the complete schema. It could be slightly more thorough about asynchronous behavior or failure modes, but the essential context is present, especially given the rich schema and 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 description coverage is 100%, with clear descriptions for all parameters including enums and defaults. The description itself adds no parameter-specific detail, but given complete schema coverage, no additional compensation is needed. Baseline 3 is appropriate.

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 uses a specific verb ('Render/export') and names the exact resource ('BlitzReels video project after timeline edits'). It also states the return value (export and job IDs) and references the sibling tool exports_list for polling, which clearly distinguishes it from related tools.

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?

The description gives clear contextual guidance: use after timeline edits, and poll results with exports_list. It does not explicitly state exclusions or alternative tools for this action, but the reference to exports_list implies the workflow and the timing is reasonably clear.

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