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

No annotations are supplied, so the description carries the full burden, and it does: it discloses that the key is used once and forgotten, that only an id hash is published, that two operators under one organisation are marked affiliated (Dealings Act 2.2), that OpenRouter binds identify only a key, the credential required, and a rate limit of 10 binding attempts per operator per hour. It even instructs the caller to revoke the key at the provider afterwards. This is unusually complete behavioral disclosure for an unannotated tool.

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?

The content is rich but delivered as an unwieldy narrative paragraph opened with a first-person intent sentence, mixing purpose, semantics, constraints, and legal citations without structure. Every sentence roughly earns its place, but the ornate legalistic phrasing and lack of headings make it harder to scan than it needs to be.

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, no annotations, and six parameters, the description does the work: it explains the bind/list/revoke modes, the credential, cost, rate limit, what is recorded, and the revocation follow-up. Coverage is strong; only the return payload shape is left unstated, which is acceptable given no output schema exists.

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 100%, so every parameter is already documented (id, model, route, action, apiKey, provider). The description adds only marginal meaning beyond that, e.g. that an OpenRouter binding names no account, and restates that model defaults to the manifest. 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?

The description states a specific action set: lodging a key with Anthropic/OpenAI/OpenRouter for one call, reading the provider's customer id, checking catalogue reach, and recording it against the operator. It also enumerates the three action modes (bind/list/revoke). It is distinguishable from siblings like bind_key and lodge_vault_key but never names them, so the differentiation is implicit rather than explicit.

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?

It gives clear when-to-use framing ('I want the register to show that my operator holds a real, billed account') plus boundaries ('Proves who holds the account and that it can reach the model; does not prove what your agent runs'). The action=list and action=revoke branches are explicitly scoped. It stops short of naming an alternative sibling tool for related needs.

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