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

With no annotations, the description carries the full burden and does well: it discloses that the response contains secrets, that nothing is stored or sent anywhere by the tool, and that manual storage plus a server restart are required afterwards. It omits whether repeated calls invalidate previously generated keys, which is the main remaining behavioral unknown.

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?

Three tight sentences, front-loaded with the purpose, then the follow-up steps, then the no-side-effect guarantee. Every sentence carries distinct, actionable information.

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 an unannotated, no-output-schema tool it covers the essentials (what is produced, where to put it, absence of side effects). However, it leaves a real ambiguity unresolved: the input schema asks for two private keys while the description says the tool creates them, and the description never explains that mismatch or whether zero-argument invocation is expected.

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% and both parameters are already documented in the schema, so the baseline is 3. The description's env-var names map to the returned secrets rather than explaining the input parameters, and it never clarifies why a key-generation tool accepts fluxIdPrivateKey/paymentPrivateKey as inputs at all.

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 specific verb and resource ('Creates two fresh private keys (WIF)') and immediately clarifies the two distinct keys and what each is for. No sibling tool generates keys, so an agent can route to it unambiguously.

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?

Gives strong post-invocation guidance (store secrets as FLUX_ID_PRIVATE_KEY / FLUX_PAYMENT_PRIVATE_KEY, then restart the server) and implies the use case (bootstrapping a Flux ID plus funding address). It never states an explicit when-not or names an alternative path, so it stops short of a 5.

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