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

Annotations only declare readOnlyHint and openWorldHint; the description adds substantial behavior the agent could not otherwise know: 22 results per page plus a total count, seller names and phones deliberately omitted, and a paid model ($0.002 USDC per successful call via x402 on Base/Solana/Arc) with failed calls not charged. The payment/pagination/omission details are exactly the kind of operational context annotations do not carry.

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 what the tool returns, then pagination, exclusions, and pricing — each sentence carries operational weight. The long returned-field enumeration is dense but justified for a listing API, though it partly duplicates the output schema.

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?

Covers pagination size, total count, and the notable absence of seller contact data, plus the payment model — enough for an agent to call it confidently. Since an output schema exists, the exhaustive field list is somewhat redundant, keeping this just below a 5.

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 four parameters (page, type, section, location) are already fully documented with slug formats and defaults. The description reinforces the type+location combination through examples but adds no new syntax, constraints, or defaults beyond the schema — baseline 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 specific verb/resource pair — Egyptian property listings from Aqarmap — scoped to sale vs. rent and to property type plus location, with concrete example queries. The source-and-country framing clearly separates it from the many other real-estate siblings (zillow, rightmove, immowelt, etc.).

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?

Usage is implied by the source/geography ('Egyptian property listings from Aqarmap') and the examples hint at the query shape ('apartment in cairo', 'villa in alexandria'), but there is no explicit when-to-use/when-not or a named alternative for other countries or other Egyptian portals. The agent has to infer that this tool covers only Aqarmap Egypt.

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