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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds context about what the tool does (browse codes) and its purpose, but does not disclose any additional behavioral traits such as pagination, result limits, or how outputs are structured. This is acceptable for a simple read-only lookup tool with an output schema.

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 two well-structured sentences. The first sentence explains what the tool b rowses, and the second adds purpose. There is no fluff, and the key information is front-loaded.

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?

This is a simple tool with two optional parameters, a rich schema, and an output schema, so the description doesn't need to over-explain. It covers the overall purpose and usage context. However, it could slightly improve by explicitly noting that either parameter option can be used independently or together, though the schema already implies this.

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 each parameter has a clear description. The tool description itself does not add extra meaning beyond the schema, but the baseline of 3 is appropriate because the schema already explains the parameters thoroughly.

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 clearly identifies the tool as a browser for NTEE classification codes, with a specific purpose: helping find the right code for searching or understanding a foundation's focus area. It uses the verb 'browse' plus the resource 'NTEE codes,' and the context about nonprofit classification distinguishes it from sibling tools about funders and grants, though it doesn't explicitly compare to a sibling.

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 states when to use the tool ('find the right NTEE code for searching or understanding a foundation's focus area') but provides no exclusions or alternatives. Since there are no direct sibling tools for NTEE codes, the guidance is adequate but not explicit about when not to use it.

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