setSpeed

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

Annotations already declare readOnly=false and destructive=false, so the safety profile is covered. The description adds a genuinely useful behavioral trait beyond annotations: 'Only the fields you pass are changed' discloses partial-patch update semantics, which an agent could not derive from the annotations alone.

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, no waste, with the core action and the patch-semantics caveat both 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?

For a 5-parameter mutation tool with 20% schema coverage and no output schema, the description covers the essential patch behavior and time units but omits the speed multiplier bounds and the projectId/openProject dependency, leaving real gaps.

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 low at 20% (only projectId is documented). The description compensates partially by clarifying 'multiplier' for the speed field and noting virtual-timeline seconds for the time fields, but leaves the speed range and id/project scoping largely to the schema.

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?

States a concrete verb set (move, resize, change multiplier) applied to a specific resource (an existing speed region) identified by id. 'Existing' implicitly distinguishes it from the sibling addSpeed, though no sibling is named explicitly.

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 phrase 'by id' plus 'existing speed region' implies this is the update path rather than the create path (addSpeed), but the description never states when/when-not to use it or names the alternative. Usage is left to inference.

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