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

Annotations already establish readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real behavioral context by disclosing that the payload mirrors /pricing.json and by distinguishing agent-completable purchases (per_call via POST /api/v1/calls from a prepaid balance) from human-only Stripe Checkout one_time purchases.

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 the core resource and then enumerates payload sections in a single dense sentence; the trailing note about /pricing.json is small and useful. It is on the long side with heavy dash-clause nesting, but every clause carries information.

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?

A read-only informational endpoint with no output schema, so the description carries the burden of describing the return contents — and it does so by enumerating bands, thresholds, features, trial, per_call and one_time. Exact field structure is still left unstated, but an agent can call this correctly with what is given.

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?

Zero parameters, so there is nothing to disambiguate; baseline 4 applies. No parameter-level claims are made that could mislead.

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 (get pricing for okgate hosted) and enumerates the payload precisely: bands, included tool calls, 80%/150% thresholds, trial allowance, per_call, one_time. It does not distinguish itself from the sibling okgate_spend_report, which an agent could plausibly confuse with pricing/rate information.

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 rather than stated: an agent reads it when it needs rates or purchase paths. It does add one actionable usage fact — that per_call is the only purchase an unattended agent can complete — but there is no explicit when-to-use vs okgate_spend_report or any exclusion guidance.

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