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

Annotations already declare the tool safe (readOnlyHint, idempotentHint, destructiveHint=false). The description adds valuable behavioral context: it returns top-N tools with full schemas, no second lookup needed, and each result is directly callable. This goes beyond the annotations, though it doesn't cover rate limits or failure modes.

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 three sentences long, front-loaded with the core purpose, and every sentence earns its place. It includes scope, usage, return format, and a prioritized call-to-action without redundancy.

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 discovery tool with only query and limit parameters, the description fully covers what it does, when to use it, and what it returns (names, descriptions, schemas, direct-call readiness). No output schema exists, so the description appropriately explains the return value, making it complete.

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 input schema fully describes all parameters with high coverage (100%), including aliases for query and default/max for limit. The description adds a list of example domains and clarifies that the query is a natural language task description, but this is marginal value over the schema's own descriptions and examples.

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's purpose: finding tools by describing a data or task. It uses a specific verb ('Find') and resource ('tools'), and distinguishes itself from siblings by positioning as a meta-tool for discovery rather than a domain-specific search (e.g., deep_research, search_within). The list of domains (SEC filings, FDA drugs, FRED, etc.) further specifies the scope.

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 when to use the tool: 'Use when you need to browse, search, look up, or discover what tools exist' and 'Call this FIRST when you have many tools available.' It also provides a when-not ('not just one answer'), but it does not name specific alternative tools, so it falls short of the 5-level criterion.

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