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

Annotations already establish readOnlyHint=false and destructiveHint=false, so the description doesn't need to restate those. It adds context about READY status and default configuration, but does not mention side effects like asynchronous job start, credit consumption, or how to track rendering progress. With no output schema, more behavioral detail would be beneficial.

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?

The description is a single, front-loaded sentence that conveys the core action, precondition, and purpose. Every phrase adds value with no redundancy.

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 1-parameter tool, the description covers the essential context: what to start, on what object, with defaults, and the intended outcome. It could mention the response format or link to get_rendering for progress tracking, but given the simplicity and schema coverage, it is reasonably complete.

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%: compel_id is described as 'The READY compel ID to render'. The description adds no new parameter-level meaning beyond echoing the READY qualifier. Baseline 3 is appropriate because the schema already documents the parameter fully.

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 clearly identifies the action ('Start rendering'), the target resource ('a READY compel'), and the intended purpose ('continue to final MP4 without opening browser UI'). It distinguishes from sibling tools like get_compel or cancel_compel by specifying the READY state requirement.

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?

It implies when to use: when a compel is READY and the agent wants to render with defaults without browser UI. However, it doesn't explicitly state alternatives or exclusion conditions (e.g., when to use cancel_compel or get_rendering), so it falls slightly short of full guidance.

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