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

Beyond readOnlyHint/openWorldHint it discloses pagination limits (30 per page, pages 1–10), that a total count is returned, that data comes through a rendering residential proxy, and a precise cost model: $0.02 USDC per successful call via x402 on Base/Solana/Arc with failed calls not charged. That payment and failure-charging detail is exactly the operational context annotations cannot 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?

The purpose is front-loaded, but the middle is a single semicolon-chained run of ~30 field names that is hard to scan and partly redundant given an output schema exists. The pricing sentence earns its place; the field enumeration largely does not.

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 paid, paginated, read-only listing tool this covers the essentials an agent needs: source, scope, page bounds, paid-call semantics, and failure billing. Return-value explanation is unnecessary because an output schema is supplied, though the long inline field list is redundant with it.

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 all three parameters (city slug, page 1–10 default 1, sale/rent default sale) are already documented in the schema. The description only restates the page range and currency context (price in INR) without adding syntax, slug rules, or validation meaning 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 and resource ('homes for sale or rent in a city') on a named source (MagicBricks India) and enumerates the returned fields, so the agent knows exactly what dataset this yields. It also names the sibling it is not (realestate_squareyards_india), letting an agent separate the two India property tools without opening either 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?

Explicitly routes the agent: use realestate_squareyards_india 'when you need Mumbai property for sale from the public squareyards.com', which is a concrete when-to-use-alternative condition. It stops short of a full when-not statement (e.g. other India or rental siblings are unaddressed), so it is clear context without complete exclusions.

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