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

Goes well beyond the readOnlyHint/openWorldHint annotations: it discloses that results are a truncated free version plus paid upgrade links, how payment works (x402 via Apify, no account needed), and exact rate limits (1 per IP per UTC day, 20 shared per ASN pool, 20 globally per day). This is precisely the operational detail an agent needs before invoking.

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?

Five dense sentences, purpose front-loaded, and each sentence carries distinct information (purpose, output, payment, usage, quota). Ordering is slightly scattered – usage guidance sits between payment and quota details – 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?

With only two params and no output schema, the description covers behavior, payment, and quotas well. The remaining gap is the omission of 'target_language' format expectations, which is the one thing an agent could plausibly get wrong when calling.

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 50%: 'text' is documented, 'target_language' has no description or enum. The description adds the 4,000-character cap for 'text' (not in the schema), but says nothing about the expected format of 'target_language' (code vs. language name) or source-language handling. Adequate but leaves the uncovered parameter unexplained.

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 (translates), resource (text), and scope (up to 4,000 characters, one text at a time). The exclusions 'not for batch work or unrestricted monitoring' separate it from siblings like classify_text, ai_extract, and summarize tools without needing 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?

'Use for one text. Not for batch work or unrestricted monitoring' gives clear when-to-use and when-not conditions. It stops short of naming the alternative tool for batch translation, so it is strong guidance but not fully routing.

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