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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the operation is free, that the underlying call was charged and completed regardless, that calling with no arguments lists recent paid calls newest first, and that results are kept for 60 minutes. These are the key behavior details an agent needs.

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 longer than two sentences but every sentence earns its place: purpose, cost model, trigger condition, timeout rationale, charge warning, usage pattern, and retention window. It is front-loaded with the core purpose and wastes no words.

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 one-optional-parameter retrieval tool with no output schema, the description is complete. It explains both invocation modes (no args to list, with `request_id` to fetch), the retention limit, and the critical billing consequence. An agent has everything needed to call 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 schema already documents `request_id` at 100% coverage, including the omit-to-list behavior. The description adds minor useful context like 'newest first' and the free-of-charge aspect, but this is mostly behavioral rather than new parameter-level meaning. Baseline 3 is appropriate.

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 names a specific verb ('Get the response'), a specific resource ('a paid call you already made'), and explicitly frames the tool as a retrieval mechanism for calls whose result never arrived. It also distinguishes itself from the `call` sibling by warning not to repeat `call`, so an agent can select 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?

It gives an explicit trigger condition ('Use it when `call` never returned'), explains why that happens (client timeout), and gives a clear exclusion: do NOT repeat `call` because it causes a second charge. This is exemplary alternative-selection guidance.

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