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

Annotations declare readOnlyHint=true, and the description adds behavioral context: 'free, AI-generated, rate-limited.' This informs the agent about rate limits and the AI-generated nature, which annotations do not cover. No contradictions.

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 one sentence but includes a redundant 'Hashtag Generator:' prefix that repeats the title. The parenthetical adds useful behavioral facts. Overall efficient but could trim the prefix.

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 simple read-only generator, the description covers purpose, key parameters, and behavioral constraints. It doesn't specify the exact return format, but 'generate relevant hashtags' implies the output is a list of hashtags. Without an output schema, this is acceptable.

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?

The schema describes 'platform' as optional with examples, but 'topic' has no description. The description mentions 'for a topic and platform,' reinforcing the parameter roles but adding little beyond the schema. With 50% coverage, description could compensate more but doesn't add constraints or output format.

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 states 'Generate relevant hashtags for a topic and platform,' specifying the action and resource. It differentiates from sibling generators like business-name-generator and content-idea-generator by focusing solely on hashtags, making selection unambiguous.

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 provides clear context that this tool is for generating hashtags given a topic and platform, implying social media use. It does not explicitly name alternatives or exclusions, but the sibling list includes many generator tools and this one is uniquely identified by name.

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