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

With no annotations, the description carries the full behavioral burden. It usefully discloses that the operation is a read and is free (no credit consumption), which is genuine behavioral context for a metered API, but says nothing about auth requirements, whether the balance is cached, or what happens for an unfunded wallet.

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?

Two short sentences, zero filler, with the core operation stated first and the cost hint appended. Every clause earns its place.

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 no-param read with no output schema and no annotations, the definition covers what is returned (wallet balance) and in what unit (USD). It stops short of describing the response shape or auth prerequisites, which would be the remaining value-add.

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?

Zero-parameter tool, so baseline 4 applies. The description correctly signals no inputs are needed and pins the output unit to USD, which is the only semantic detail that matters here.

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+resource ('Return the wallet balance') plus the unit (USD), which is more than a restatement of the name. It does not distinguish itself from adjacent reads like fikra_get_account or fikra_get_usage, so an agent must infer the split.

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 word 'Free' hints that calling this costs no credits, which is implicit guidance, but there is no statement of when to prefer this over fikra_get_account (balance vs. account details) or fikra_get_usage. Usage is implied rather than specified.

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