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

Annotations already declare readOnlyHint and openWorldHint. The description adds valuable context: it wraps an external tracker, lists data sources (Crunchbase News, TechCrunch, sector press) and returned fields (company, amount, round type, investors, date), and notes a maximum look-back of ~180 days. This exceeds what annotations alone provide.

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 very concise: one sentence for purpose, one for wrapper, one for return fields, and a clean bullet-like listing of args. No redundant information, every sentence 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 simple read-only query tool with three optional parameters and no output schema, the description provides essential context: purpose, parameters, data sources, and return fields. It lacks details on pagination or typical result size, but given the tool's simplicity, it is sufficiently 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?

Schema coverage is 0%, but the description fully compensates by explaining each parameter: 'stage' with example values like 'seed'/'series a', 'sector' with examples like 'ai'/'fintech', and 'days_back' with default (30) and max (~180). This adds complete semantics beyond the bare schema.

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 states the verb 'track' and the resource 'startup funding announcements'. It specifies filtering by stage and sector, and distinguishes itself from sibling tools (e.g., sales-intelligence tools for enrichment or lead finding) by focusing uniquely on funding announcements.

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 provides clear context for when to use the tool (to fetch recent startup funding by stage/sector) but does not explicitly mention when not to use it or suggest alternative tools. The filtering options imply usage scenarios, and the sibling list shows no direct overlap, but explicit exclusions are missing.

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