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

The description adds useful behavioral context beyond annotations: 'Verified daily — dead links auto-removed' indicates data freshness and maintenance, and 'Free, no auth' clarifies access requirements. The readOnlyHint, idempotentHint, and openWorldHint are already covered by annotations, so the description supplements rather than repeats them.

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 well organized: a clear value proposition with examples, freshness/access notes, then usage guidance. The 'When to use / When not to use' bullet is a nice structural touch, though somewhat generic in content.

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 an optional-parameter, read-only lookup tool with an output schema and rich param docs, the description covers the main invocation facts: no auth, data freshness, recommendation behavior, and empty-stack behavior. The usage guidance is slightly generic, but nothing needed to call the tool is missing.

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 100%, with each parameter already well-documented (examples, enum values, default, empty behavior). The description's mention of 'pass your tech stack' reinforces the stack parameter but adds no meaning beyond what the schema provides.

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 a specific resource ('AI and cloud startup credit programs') and the tool's purpose ('live, verified index' with matched recommendations). It distinguishes itself as a credit-program lookup domain, though it doesn't explicitly contrast with sibling tools.

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 includes 'When to use' and 'When not to use' sections, but the guidance is generic ('when the user's request matches this capability') and doesn't specify concrete triggering scenarios or name alternative tools. It gives some exclusion guidance, but no real decision framework.

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