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

Annotations already declare readOnlyHint=true and idempotentHint=false, so the safety profile is covered. The description adds that it returns timing metrics for a vault key, but does not explain what those metrics include or why idempotency is marked false for a read. That is a modest addition beyond structured fields.

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?

It is a single front-loaded sentence with no filler. It is efficient, though it could have used one clause to differentiate from sibling keygen tools.

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 one-parameter read tool with full schema coverage and readOnlyHint annotations, the description carries enough to call it correctly. The only gap is sibling differentiation and what the timing metrics contain, which are minor given the simple interface.

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%, with the single pubkey parameter documented as a 'thorpub...' vault public key. The description matches the schema's meaning but adds no format examples or lookup caveats beyond it, so baseline 3 applies.

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 verb ('Returns') and resource ('keygen timing metrics'), and scopes it to a vault public key. It does not distinguish itself from nearby siblings like get_keygen, get_keysign, or get_tss_metrics, which also concern keygen/key operations.

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?

There is no guidance on when to use this versus get_keygen or get_tss_metrics, nor any prerequisites or exclusions. The only usage signal is the implicit 'for a specific vault public key', which is just the parameter requirement.

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