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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuine context beyond that: the credit cost ('Flat 5 points per successful run') and the shape of the payload returned, which no annotation conveys.

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?

One sentence for purpose and return contents, one short sentence for cost. Front-loaded with the verb and lookup key, zero filler.

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?

No output schema exists, but the description enumerates the returned fields (name, tagline, makers, topics, screenshots, similar startups), which largely compensates. Minor gap: no note on error behavior when a slug is unknown or on how the URL form is parsed.

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% and the single parameter is already documented with an example ('e.g. iconscove'). The description restates 'slug or URL' but adds no format nuance beyond the schema, so the baseline 3 applies.

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 ('Get one startup from BetaList') plus the lookup key ('by slug or URL'), and enumerates the returned fields. The phrase 'one startup' cleanly separates it from run_betalist_startups_search and run_betalist_startups_latest without needing to name them.

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 implied rather than stated: an agent can infer this is the tool to use when it already holds a slug or URL. There is no explicit when-to-use/when-not guidance and no named alternatives, even though three sibling BetaList tools exist that could confuse selection.

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