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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds real behavioral context beyond them: it discloses that the returned deals do not include promo codes and that codes must be obtained on the Microlaunch site. That is a non-obvious output limitation an agent could otherwise waste a call trying to work around.

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?

A single compact sentence that front-loads the primary action, then adds the optional filter, then the caveat. No padding and nothing buried.

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 one-parameter, read-only listing tool with full annotation coverage and no output schema, the description covers the resource, the filter, and the key limitation on returned data. Only the shape of the result list (fields per deal, pagination) is left unstated, which is minor here.

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% and the single category parameter is documented with examples ('ai, marketing'). The description adds only that the filter is optional and slug-shaped, which the schema already conveys with required: [] and its maxLength/description. Baseline 3 is appropriate.

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 concrete verb and resource: 'List active discounts and lifetime deals from indie makers on Microlaunch.' The scope (active deals only, filtered by category) makes it clearly distinct from browse_category, get_product, and top_launches, though it never names a sibling to route against.

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?

'Optionally by category slug' implies the filtering use case, and 'Codes are revealed on Microlaunch, not here' sets an expectation about what the agent can do with the result. But there is no explicit when-to-use or when-not-to-use guidance relative to the sibling tools, so usage is only implied.

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