nessie_list_customers

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint=false. The description adds the explicit 'Read-only' phrase and the authorization scope ('available to the configured API key'), which slightly enriches the behavioral context but does not disclose additional traits like pagination or return format. No contradiction with annotations.

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, front-loaded sentences with no filler. The core scope ('List all Nessie customers') leads, and the safety note follows. Every word earns its place.

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, read-only list operation with no output schema, the description is essentially complete. It clearly states what is listed and under whose scope. A minor gap is the lack of explicit return shape, but the verb 'List' implies a collection.

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 there is nothing for the description to clarify. The schema is an empty object, and 100% coverage is vacuously true. Baseline for no parameters is 4.

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 ('List'), a clear resource ('all Nessie customers'), and a scope qualifier ('available to the configured API key'). This clearly distinguishes it from sibling tools like nessie_get_customer (single customer) and nessie_list_accounts (accounts, not customers).

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 gives clear context: use this to list all customers accessible via the configured API key. However, it does not explicitly name alternatives or state when not to use it, leaving some sibling differentiation to inference.

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