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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds genuine value beyond that: it discloses the polling nature, the GET endpoint, and the return shape with status values pending|running|done|error. It doesn't mention rate limits or polling cadence, so not a full 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?

Three front-loaded sentences with the purpose and triggering action stated first. The raw endpoint line is slightly redundant but earns its place by anchoring the request shape. Minimal waste overall.

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?

There is no output schema, and the description compensates by stating the return shape ({ operation }) and the status enum. With annotations covering safety and both params documented, an agent has everything needed to call and interpret it.

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% and both params are already documented (app name/id, operation_id from Location header). The description maps them onto the URL path and repeats the Location-header origin of operation_id, adding only marginal meaning 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?

States a specific verb (poll the status) and resource (asynchronous operation), and clarifies its role relative to sibling actions like scalingo_scale_app and scalingo_restart_app by noting those return an operation to track. An agent can distinguish it from the generic scalingo_request without opening the schema.

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?

Explicitly says when to use it: after a scale or restart returns an operation to track. This provides clear context for invocation. No explicit exclusions or named-alternative comparison, which keeps it just below a 5.

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