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

Annotations already declare readOnlyHint=true, so safety is covered; the description usefully adds that the call requires an authenticated context, that it takes no targeting arguments, and roughly what comes back ('Returns { user }'). It stops short of documenting failure modes for expired/invalid tokens.

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 short clauses with zero filler: what it fetches and its fields, the exact API route, and the return envelope. The most useful information (scope and payload) is 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?

With no output schema, the description compensates well by listing the returned fields and the response envelope, which is what an agent needs to plan downstream use. Only auth/error behavior is left implicit.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate. The baseline for a no-param tool applies, and the description correctly signals no inputs are needed.

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 and resource ('Fetch the authenticated user's account'), enumerates the returned fields, and gives the exact endpoint (GET /v1/users/self). This cleanly distinguishes it from the app-scoped siblings such as scalingo_get_app and scalingo_list_apps.

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 'authenticated user's' implies the use case (resolving the caller's own identity), but there is no explicit when-to-use statement, no prerequisites, and no reference to alternatives. Usage is inferable rather than stated.

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