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

Beyond the readOnlyHint annotation, the description adds important behavioral context: the data is untrusted citizen-authored, the server-owned provenance boundary lives in CallToolResult _meta, and the call is side-effect-free. This goes well beyond the annotation and helps the agent trust and interpret results correctly.

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 compact and front-loaded, with each sentence delivering distinct value: what is read, auth requirements, data trust characteristics, and safety. No filler or redundant restatement of the tool name.

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 parameterless read-only tool with no output schema, the description covers the return contents, the trust model, the provenance mechanism, and the safety profile. An agent has everything needed to invoke and interpret this tool 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 has no parameter semantics to clarify. The baseline of 4 applies, and the description appropriately focuses on what the tool returns rather than parameter usage.

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 ('Read') with a clear resource ('the society's public books') and enumerates specific contents (ledger rows, holdings by tier, live on-chain balance, verification recipes). This makes the tool's purpose unmistakable and distinguishes it from sibling tools that read individual records or perform mutations.

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 'No auth needed' and 'READ-ONLY: this call changes nothing and can be repeated safely,' giving clear context for when this tool is appropriate. It does not name alternatives or exclusion conditions, but for a parameterless public read tool this is sufficient practical guidance.

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