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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuinely new behavioral context absent from structured fields: the call costs $0.50 in USDC via x402 and settles on Base, Solana, Polygon or Arbitrum — critical for an agent to know before invoking. It stops short of describing rate limits, retry behavior on payment failure, or pagination.

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?

Two sentences, zero waste: purpose and scope first, then the payment prerequisite. Every clause earns its place and nothing is buried.

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 does partially explain the return: permit records plus counts by category. For a simple two-parameter paid report, this covers what an agent needs to decide to call it, though it omits output field detail, pagination, and payment-failure behavior.

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% with enums for both jurisdiction and category, so the schema carries the documentation load. The description adds only the 'one area' constraint, implying jurisdiction is a single value, but gives no guidance on how category interacts with the category-level counts in the output. Baseline 3 is appropriate when the schema is this rich.

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: 'All building permits issued in the last 7 days for one area, with counts by category.' This distinguishes it from broader siblings like search_permits or permit_history_for_address by its fixed 7-day window and per-area aggregation, but it never names those alternatives explicitly, so sibling differentiation is only implied.

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 constraints ('last 7 days', 'one area'), which signal it is not for custom date ranges or multi-area queries, but the description never states when to prefer permit_stats, permit_trends, or count_permits instead. No exclusions or prerequisites are given beyond the payment notice.

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