Recover a handle with your key

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

Beyond the annotations (which only mark it as a non-read-only, non-idempotent, non-destructive write), the description adds real behavioral detail: a two-phase flow, a one-time challenge, and a 5-minute validity window. It stops short of covering failure modes such as an invalid signature or an unregistered key.

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?

A single dense sentence that front-loads the triggering scenario, then the workflow. Nothing is wasted, though the packed structure asks the reader to unpack the two-call flow themselves.

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, the description correctly states what each call returns ('a one-time challenge', 'a new handle_token') and the full call sequence. It omits error/edge-case behavior for a recovery operation, leaving a modest gap.

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 only 33% (challenge and signature are undocumented there), so the description carries the load and does explain each parameter's role: pass handle alone to get the challenge, then return challenge plus signature. This meaningfully compensates for the schema gap, though it gives no format details.

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 concrete verb and resource: recover a handle_token via a signed challenge-response. The precondition ('lost your handle_token but still have the private key you registered') implicitly separates it from register_key, but no sibling is named outright, so it falls short of the top tier.

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 opening question gives a clear situational trigger for when to call this tool. It does not state when NOT to use it or point to register_key as the alternative for the no-key case, so no exclusions are offered.

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