Who am I

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

Annotations only declare readOnlyHint and openWorldHint; the description adds substantial behavior: the exact identity fields surfaced, that the API key is never returned (only its source: environment or credentials file), and that the call fails with a hint pointing at gamealia_login when unauthenticated. The one restatement of "read-only" is minor against the added security and error-path context.

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?

Front-loaded with the result contents, then scope, then the alternative, then the failure mode — a sensible order with no filler sentences. The parenthetical field list is dense but every item is informative, so it is length justified by content rather than padding.

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 enumerating what is returned, so an agent knows what to expect from the response. It also covers the unauthenticated failure case and the key-handling boundary, leaving no material gap for a simple identity-check tool.

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 schema is an empty object at 100% coverage. Baseline for a no-parameter tool applies, with no parameter-level meaning to add.

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 ("Shows who is signed in") and enumerates the returned fields: user id, username, developer profile existence, active developer account with role, API URL, and key origin. It also explicitly separates itself from the neighboring account tool ("to list or switch accounts use gamealia_accounts"), so an agent can distinguish it from siblings without opening a 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?

Gives an explicit when-to-use ("confirm the login before creating or publishing games"), names the alternative for a related need (gamealia_accounts for listing or switching), and names the recovery path (gamealia_login) when the call fails. When, when-not, and alternative are all present.

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