Add an SSH public key

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

With no annotations, the description carries the full burden and delivers: lifecycle behavior (removed when credential is revoked), acceptance criteria (Ed25519, ECDSA, security-key forms, RSA >= 3072), explicit refusals (DSA, short RSA, certificates, option lines, multiple keys), cardinality limits (one person per key, eight per person), and a safety warning against private keys.

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?

Purpose is front-loaded in the first sentence, and the accepted/refused enumerations, while dense, each carry actionable constraint information that earns its space. It runs long but contains no filler or redundancy.

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?

For a mutation tool with no annotations and no output schema, the description covers authorization context, input constraints, lifecycle, and limits comprehensively. The only omission is any indication of what the call returns, which is a minor gap given the absence of an output schema.

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 the baseline is 3, but the description adds genuine param-relevant meaning: the accepted/refused algorithm list, the one-key-per-line constraint, and the 'never send a PRIVATE key' warning are not in the schema. It adds nothing for the 'name' parameter, which the schema already documents fully.

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?

Opens with a specific verb+resource ('Register an OpenSSH public key') and scopes it to the person the API key belongs to. It is unmistakably distinct from its siblings list_ssh_keys and remove_ssh_key without any schema lookup.

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 description establishes context (the key works only on computers with SSH enabled in the acting account, and is removed on credential revocation), which implies when it is applicable. However, it never explicitly routes the agent among alternatives (e.g. set_computer_ssh, remove_ssh_key) or states when not to call it, so the guidance is inferable rather than explicit.

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