account_status

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

No annotations are provided, so the description carries the full burden, and it largely does: it enumerates what is reported (key label, usage today/week/month/total, spending limit, remaining credit) and handles the in-progress sign-in case with a status and link. It stops short of stating prerequisites (e.g. behavior when not signed in) or read-only guarantees.

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?

Four short sentences, front-loaded with the core purpose followed by returned data, usage triggers, and the no-parameter note. Every sentence adds something, though the return-value inventory is somewhat list-heavy.

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 annotations and no output schema, the description must explain returns, which it does in detail, and it supplies usage triggers. It is close to complete for a zero-parameter status tool, missing only edge-case behavior such as the not-signed-in response.

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, which sets a baseline of 4, and the description usefully confirms this with 'Takes no parameters.' There is nothing further to document.

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 ('Show whether this computer is signed in to OpenRouter, with the key's spending') and is clearly distinguishable from siblings like auth_login/auth_logout, which are actions on the same auth state. An agent can tell what this returns 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?

Gives explicit triggers: 'after auth_login to confirm sign-in finished, or when the user asks about cost, usage or credits.' It names the sibling it follows but does not state when *not* to use it or contrast it against any alternative status source, so it falls short of the 5 bar.

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