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 genuinely useful behavior beyond that: results are sorted 'most searched first' and each entry exposes a defined set of attributes. It omits pagination/result-limit behavior, keeping it out of the top band.

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 dense sentence, front-loaded with the resource and its ordering ('Every ... template, most searched first'), followed by a compact colon-list of returned fields and the filter note. The field list is long but each item earns its place by telling the agent what the results contain.

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?

With no output schema, the description correctly compensates by enumerating the returned fields (scenario, photo count, roles, length, aspect ratio, pet support, page) and the ordering. With zero required parameters, two well-documented optional filters, and read-only annotations, nothing an agent needs to invoke this correctly is missing.

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 both parameters carry their own descriptions, so the schema already does the heavy lifting. The description restates the two filters in prose ('number of people in the video', 'pets') without adding format or edge-case detail, matching the baseline 3.

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?

Specific verb (list) plus resource (meme video templates) with explicit scope ('Every ... template'), plus an enumeration of exactly what each template entry contains. None of the siblings (get_faq, how_to_make, recommend_settings, get_example_prompts) overlap with browsing templates, so the agent can route unambiguously.

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 states the available filters ('Filter by the number of people in the video or by pets'), which tells the agent how to narrow results. It does not, however, state when to prefer this over a sibling or any exclusion conditions, so it stops short of full when/when-not guidance.

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