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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the agent knows this mutates state, and the description's 'Update' verb agrees with them. Beyond that, it adds only the constraint that the target must be a supported structured step and must live in a draft endpoint; it does not say whether unspecified fields are preserved or wiped, which matters greatly for an update of a complex oneOf payload. With annotations covering the safety profile, a 3 is appropriate.

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?

A single tight sentence with no filler, and the verb-plus-resource is front-loaded. It is efficient but borderline under-specified for a tool with a deeply nested schema.

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?

An output schema exists, so return values need not be explained, but the input side is complex, involves five mutually exclusive step shapes, and has zero description coverage. Nothing tells the agent how an update interacts with existing step fields or which types are 'supported', leaving a significant gap.

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%, so the description carries the full burden, yet it mentions none of the four required parameters (apiId, endpointId, stepId, step) or the five step-type variants. The one phrase 'structured step' gestures at the step payload but adds no usable semantics; at 0% coverage the description does not compensate.

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 specific verb (Update) and resource (a structured step in an API draft endpoint), and the naming/output shape lets an agent distinguish it from step_create, step_delete, and step_reorder. The qualifier 'supported structured' is vague about which step types are updatable, but the core action is unambiguous.

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 no when-to-use context, no prerequisites, and does not point to alternatives such as step_create for new steps or step_delete for removal. Only the phrase 'in an API draft endpoint' hints at the required context, and that is inferred rather than stated.

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