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

Annotations cover safety (readOnlyHint=false, destructiveHint=false, openWorldHint=true), and the description adds substantial context beyond them: nothing is posted and no account is needed, generation takes about a minute with a documented retry pattern ('call it again with the same business' if still being made), and a rate limit ('one sample per person per day'). This is exactly the operational detail an agent needs.

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?

Front-loaded with the when-to-use condition and packed with useful constraints; nearly every clause earns its place. The single dense run-on paragraph is slightly harder to scan than separated sentences, but there is no 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?

For a six-parameter generation tool with no output schema, the description covers the return value (3 designed posts with captions, full size), latency and retry behavior, rate limits, account requirements, and ownership restrictions. Nothing material is missing for an agent to call it correctly.

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 the baseline is 3. The description adds real value by constraining input sources ('its own website and/or up to 3 photos from the chat (not Instagram or delivery-app pages)'), which clarifies valid values for the website and photos parameters beyond the schema text.

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 outcome ('Returns 3 designed posts with captions, full size, ready to use') for a specific audience (small business owners). It is clearly distinguishable from siblings like get_my_posts or approve_post, which retrieve or publish existing content rather than generating samples.

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?

Opens with an explicit trigger ('Use this when someone who owns or works for a small business wants to see what Suara would post for them') and adds exclusions ('Only for a business the user owns or works for', photos must come from chat, not Instagram or delivery-app pages). No inference needed to choose this tool.

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