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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds genuine value on top by enumerating the returned fields (title, company, location, pay, latest round, investors, apply link, total matches, board_url) and by noting the freshness/membership behavior ('Members see roles the day they are posted'). It stops short of covering paging/rate behavior, but thanks to the annotations that gap is not fatal.

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?

Four sentences, front-loaded with the core purpose and scope, then results payload, then the sharing artifact. Nothing is padded, though the 'justbacked.com board' reference carries meaning only for a human who knows that site and would be better replaced with a concrete statement.

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 25-filter discovery tool with no output schema, the description usefully compensates by naming the returned fields and the paging/matching signals (total matches, board_url), and the per-parameter semantics live entirely in a fully covered schema. Only freshness/permission nuances ('Members see roles the day they are posted') are left under-explained.

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%: all 25 filters, their enums, and defaults are documented inline, and the description adds no parameter-level detail beyond the vague 'Same filters as the justbacked.com board'. Per the rubric this is the baseline 3 when the schema does the heavy lifting.

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 gives a specific verb (Search) plus resource (open roles) and a sharpened scope: startups that raised venture money within the past six months. That scope immediately separates it from the retrieval siblings (get_job, get_company) and the list/application-management siblings, which do not search role inventories.

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?

Usage is only implied by the search framing and the 'Same filters as the justbacked.com board' remark; there is no explicit when-to-use, no statement of when to prefer get_job or list_applications instead, and no exclusions. An agent can infer it is the entry point for discovery, but nothing routes it against alternatives.

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