Show the configured Flux identity and balance

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

With no annotations, the description carries the full behavioral burden and does reasonably well: it discloses the return contents, the missing-key edge case behavior ('explains what to configure'), and a security guarantee ('never returns private keys'). It does not cover permissions/authentication requirements, but for a zero-param local read tool this is solid disclosure.

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 what is returned, followed by the missing-keys note and the private-key guarantee. 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?

There is no output schema, so the description must describe the return values, and it names the exact fields (Flux ID, payment address, spendable balance, USD value). It also covers the missing-key scenario. It is essentially complete for a zero-param query tool, with only auth/permission context unaddressed.

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?

The tool takes no parameters (zero-param schema), so per the rubric the baseline is 4. The description appropriately spends its words on return semantics instead of nonexistent inputs.

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+resource: it returns the Flux ID, payment address, spendable FLUX balance, and USD value. This clearly distinguishes it from app-lifecycle siblings (flux_deploy_app, flux_get_app) and from flux_generate_keys. It stops short of explicitly naming a sibling to differentiate against, so it lands at a strong 4.

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?

Usage is implied rather than stated: an agent can infer this is the identity/balance check, and the 'explains what to configure if keys are missing' clause supplies a conditional scenario. There is no explicit when-to-use versus when-to-use-something-else guidance or named alternative.

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