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

No annotations are provided, so the description carries the full burden. It does disclose genuinely useful behavioral context that the schema cannot: a per-call price of $0.20 and the x402/USDC-on-Base payment mechanism, which matters for an agent deciding whether to invoke. But it says nothing about what recall actually does behaviorally, such as whether it reads from a persistent store, what it returns, or any latency/auth characteristics.

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 with the purpose front-loaded and the pricing second; neither sentence is padding. It is efficiently sized, though it is arguably under-specified rather than truly concise.

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?

With no annotations, no output schema, and a paid invocation model, the description should explain more than it does: what recall returns, whether it is stateful, and how it differs from rag_query or chatbot. The payment disclosure is a plus, but the behavioral picture for an agent is largely missing.

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?

Schema description coverage is 100% and there is a single documented parameter, so the schema already explains 'prompt'. The description adds no additional semantics about how the prompt is interpreted or what form it should take. Baseline 3 applies when the schema does all the work.

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 verb-ish action (recall/retrieval) and a resource (memory/context), so the general intent is inferable. However, it is generic enough to be confusable with siblings like rag_query, longform_qa, or chatbot, and it never clarifies what 'memory' or 'context' refers to or what scope of retrieval is offered. Minimum viable rather than distinguishing.

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?

There is no statement of when to use this tool versus the many similar sibling tools, nor any prerequisites or exclusions. The only usage-relevant signal is the pricing note, which tells the agent a call costs money but not when a call is warranted.

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