spend_policy

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

With no annotations, the description carries the full burden and does disclose the key behavioral trait: it is read-only. It also compensates for the absent output schema by enumerating the return payload (sha256, rolling budgets spent/remaining, per-host spending, ledger path and integrity). It does not discuss error modes or refresh semantics, so not a 5.

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?

It is a single dense sentence with the core concept ('the spend policy this server enforces') front-loaded, followed by the fields returned. It reads as a field dump rather than prose, but every clause earns its place given the missing output schema.

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, non-mutating introspection tool with no output schema and no annotations, the description supplies both the read-only guarantee and a field-level preview of the response. Only minor gaps remain, such as failure behavior and whether the policy can change between calls.

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 takes zero parameters, so the baseline is 4. No parameter semantics are needed or offered, and none are missing.

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 the resource (the server's enforced spend policy, AGENTWALLET_POLICY) and enumerates its contents, which tells an agent what data this returns. It is clear but does not distinguish itself from neighbors like get_usage or get_x402_revenue, and it describes the payload more than the action, so it stops short of a 5.

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 call this versus alternatives such as get_usage, check_approval, or list_wallets. The mention of 'whether the connected client can answer approval questions' touches on approval context but gives no routing guidance.

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