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

With no annotations, the description carries the full burden and does well: it declares cost ("Free"), the rate limit ("50 calls/day per client"), and the return shape ("compact cards (no citations)"). It does not state pagination/result-count limits or that empty filters return a broad listing, so it is strong but not exhaustive for a zero-annotation tool.

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 question followed by tightly packed clauses covering scope, cost, return format, alternative tool, and rate limit in four sentences. Dense but every clause carries information; only the slight redundancy between the question and the second sentence costs a point.

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 six-parameter, fully-documented, filter-only search tool with no output schema and no annotations, the description supplies cost, rate limit, result format, and the escalation path to get_provider. What is missing is minor: no note on result count/pagination or behavior when all optional filters are omitted.

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 schema already documents all six parameters with format examples. The description mostly restates those facets, adding only the mild nuance that country means on/off-ramp coverage; baseline 3 is appropriate when the schema does the heavy lifting.

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?

Opens with a concrete question that names the resource (payment/stablecoin providers) and the exact facets searched (asset, chain, country, service/category). It also explicitly distinguishes itself from the sibling get_provider, so an agent can separate the two 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?

"use get_provider for the full cited record" names the alternative and the condition that selects it, and the leading question frames the intended query context. No explicit when-not guidance (e.g., do not use for name-only or non-provider lookups) is given, so it stops short of a 5.

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