Lynceus credits balance

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

With no annotations provided, the description carries the full burden. It explicitly states 'Free; no side effects,' which discloses that the operation is read-only and has no impact. This is meaningful behavioral context beyond the verb 'check.' It does not describe the return format, but for a balance check this is arguably self-evident. The disclosure is sufficient for the tool's simplicity.

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 sentences, front-loaded with the core purpose, then usage context, then a side-effect note. Every clause earns its place. No fluff, no repetition. The structure is optimal for an agent to quickly understand the tool's function and applicability.

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 zero-parameter, no-output-schema tool, the description is complete. It covers purpose, when to use, and that it is free and side-effect-free. There are no prerequisites, permissions, or return-value details needed beyond what is obvious. The description fully equips an agent to decide whether and how to invoke it correctly.

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 has zero parameters, so the description does not need to explain any. The schema has no properties, and the description adds no parameter-specific meaning. Baseline for 0 params is 4, and there is nothing else to say. The description's focus on usage and side effects is appropriate; no parameters to document.

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 clearly states the action ('Check the Lynceus account's remaining credits') with a specific verb and resource. It aligns with the title. However, it does not explicitly differentiate from sibling tools (lyn_search, lyn_extract), though the resource and verb make it distinct. It could have named the siblings, but the purpose is unambiguous.

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 description gives clear context for when to use the tool: 'when the user asks about balance/credits' and 'after a 402 insufficient_credits error to confirm the situation.' It does not explicitly mention alternatives or exclusions, but the use cases are specific and the 'Free; no side effects' note provides additional guidance. No need to exclude since the operation is standalone.

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