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

Annotations already cover the safety profile (readOnly, non-destructive, idempotent, open-world), so the description's job is to add context beyond that. It contributes two genuinely useful facts: no authentication is required, and billing is pay-per-event on Apify. It does not explain pagination or how the unified row layout behaves, but that is secondary for a read-only tool.

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?

Four short sentences, front-loaded with the capability statement before the coverage exclusions and billing note. Slight redundancy from listing the platform set twice (once for coverage, once implicitly against the excluded list), but nothing is wasted.

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 ten optional parameters, no required fields, and no output schema, the description supplies the essentials: what the output shape is ("one row layout across platforms"), auth requirements, and cost model. It could be more explicit about how charges accumulate per returned row, but the critical calling information is present.

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%, so the schema already documents all ten parameters including defaults and caps. The description adds no parameter-level meaning beyond what the schema states, so the baseline of 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 concrete verb and resource ("Search public posts and comments") and explicitly names both operating modes: keyword search across six named platforms, or reading comments on given post addresses. It also names the platforms that are NOT covered, so an agent knows the boundary of the tool without reading the schema.

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 two usage modes are spelled out clearly, along with the "No login" prerequisite and the explicit exclusion of Instagram, X, Facebook, TikTok, and LinkedIn. There are no sibling tools to route against, so the absence of an alternatives section is not a real gap.

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