liveauth_mcp_usage

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

No annotations are provided, so the description must carry the full burden. It does disclose a key behavioral trait: 'without making a charge' indicates the call is non-destructive and free. However, it doesn't clarify whether the usage query itself counts as a call or affect the budget, nor does it explain any side effects or limit conditions. This is a minor gap for a read-only usage tool.

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?

The description is two sentences long, front-loaded with the core purpose, and contains no filler. Every word contributes to understanding the tool's function and when to use it.

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 simple tool with no parameters and no output schema, the description is complete. It clearly states what it queries (usage and remaining budget), the metrics (sats and calls), and the key safety aspect (no charge). No additional context is necessary.

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 baseline is 4. The description adds no parameter details, but none are needed. It correctly focuses on the tool's purpose and usage rather than param syntax.

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 uses a specific verb 'Query' and identifies a clear resource: 'current usage and remaining budget for the MCP session.' It also distinguishes itself from siblings like 'status' and 'charge' by focusing on budget/calls usage, making the purpose 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 explicitly states when to use the tool: 'Use this to check how many sats and calls have been used without making a charge.' This provides clear context and implies it's a non-charging alternative to 'liveauth_mcp_charge'. It doesn't explicitly name alternatives or exclusions, but the guidance is practical and sufficient.

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