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

Annotations already declare this is a non-read-only, non-idempotent mutation with no destruction. The description adds that it 'initiates the process to actually add the subtitle,' clarifying the finalization behavior. It does not mention idempotency risks, error handling, or what happens if upload_responses are incorrectly marked.

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 the prerequisite and the action. Every sentence contributes to understanding the workflow. It could be slightly tighter, but there is no wasted text.

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. The description sufficiently explains the workflow context for this finalization tool. Minor gaps remain around failure modes and idempotency, but the core calling context is 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 description coverage is 100%, so both parameters are already documented in the schema. The description adds no additional syntax or format details beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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 states a specific action: finalizing the subtitle addition after PUT uploads. It distinguishes this completion step from the earlier upload call (likely upload_subtitles) by describing the workflow. It does not name the sibling tool explicitly, but the verb+resource combination is clear.

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 clearly states the prerequisite sequence: add subtitles first, receive URLs, complete PUT requests, then call this. This is explicit when-to-use guidance tied to a workflow. It does not discuss when not to use or alternatives beyond the implied earlier step.

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