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

Annotations already declare readOnly/idempotent/non-destructive, and the description still adds substantial behavior: eligibility dimensions checked (stage, funding gate, raised-amount cap, company age, region), needs-first ranking, exclusion of paused/closed programs, a 25-result ceiling, dedup rules ('one program per provider, cloud counted once'), and the caveat that values are headline maximums not guarantees.

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?

Purpose and routing are front-loaded and most sentences carry information. The parenthetical provider roster (AWS Activate, Google for Startups, NVIDIA Inception, Stripe Atlas, Mercury, HubSpot...) is longer than needed to convey scope, and the single dense block would scan better split into routing/behavior/returns.

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 12-parameter tool with no output schema, the description covers the eligibility model, ranking order, exclusions, result cap, per-result payload (value, qualify + why, how to claim, link) and the claimable-total caveat. An agent has everything needed to call it correctly and describe results to a user.

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%, so baseline is 3, but the description adds real meaning by mapping the eligibility logic onto specific parameters (stage, funding, raised-amount cap, company age, region) and explaining that 'needs' drives category ranking. It does not explain the priority enum tradeoffs or include_gated/only_qualifying interaction beyond what the schema says.

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?

States a specific verb and resource — rank startup credits/perks/deals a given company can claim from a 2,800+ program catalog — and names the two sibling tools and how they differ. An agent can distinguish it from search_startup_perks and get_startup_perk without opening any schema.

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?

Gives an explicit trigger ('when the user describes their own startup and asks what they can get or qualify for') and explicit alternatives with their selecting conditions ('search_startup_perks to look up a provider or topic without a company profile', 'get_startup_perk for one program's full terms'). Routing is unambiguous.

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