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

Annotations already declare idempotent=true, destructive=false, closed-world, and that it is a non-read operation. The description adds genuinely new behavioral context: request size limit (65536 bytes), 5 s execution bound, 'software/model evidence only', and that a candidate is returned only when verified. It still does not explain what is mutated or authorization needs, keeping it from a 5.

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 terse Problem/Input/Result/Limits structure is well front-loaded and dense with no filler. Every clause carries information, though the telegraphic style is slightly terse for a complex optimization tool.

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 explained, and the description covers input content, execution limits, and the conditional-verdict behavior. It is nearly complete for a mutation tool, missing only explicit prerequisite/permission context.

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 0% across 4 required params, so the description must compensate. It usefully characterizes the payload (trajectory, maximum speed, maximum duration) but does not explain idempotency_key, max_total_price, or schema_version semantics, so it only partially fills the 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 verb (Optimize) and resource (a bounded trajectory) and scopes it with the gating condition that speed and duration constraints must pass. This is clearly distinguishable from sibling validation tools by its optimization outcome. However, it does not name or contrast any specific sibling, so it falls short of a 5.

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 states a precondition (only when speed and duration constraints pass) but gives no explicit when-to-use guidance versus alternatives. With many related siblings (validate_trajectory_timing, reconstruct_smoothed_trajectory, validate_kinematic_dynamic_limits), the agent gets no routing help.

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