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

With no annotations provided, the description carries the transparency burden. It discloses that the server validates the RSA-4096 public key, computes the key ID, and never sees the password because the private key is already encrypted client-side. It does not mention whether uploading replaces existing keys or what the return payload is, but the security-critical behavior is well covered.

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 description is compact and front-loaded with the core purpose, followed by two essential context blocks: the security note and the access/auth instruction. Every sentence earns its place; no filler or redundant repetition of the schema.

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 mutating tool with no annotations and no output schema, the description covers purpose, validation behavior, security posture, and authentication requirements. It could be more complete by stating that the HITL config must already exist or by describing the result of a successful upload, but the provided context is sufficient for correct invocation in most cases.

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 coverage is 100%, so the schema already documents all four parameters. The description adds context about RSA-4096 and client-side encryption, but largely reinforces what the parameter descriptions already say rather than introducing new semantics.

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 ('Upload an encryption keypair') and a specific target ('for a HITL config'), with concrete details about validation and key ID computation. This clearly distinguishes it from related siblings like get_hitl_keys and delete_hitl_keys.

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 gives explicit access context: a Proof account is needed, the client must authenticate first, and start_login does NOT open this tool. It does not explicitly state the ordering relative to create_hitl or when to use it instead of other HITL tools, but the auth flow guidance is clear and useful.

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