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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), so the bar is lower, yet the description still adds real behavioral context: the call is free, it returns only active providers, and pending applications gate on owner/administrator authorization. That auth-condition disclosure is genuinely useful for an agent deciding whether the call will succeed.

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?

Three short fragments with zero filler, and the most decision-relevant fact (FREE) is front-loaded. It is arguably too terse given the sibling ambiguity, but nothing in it is wasted.

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 an output schema present, return values need no explanation, and the parameter is fully documented in the schema. The remaining gap is sibling differentiation from provider.describe, which matters given the crowded toolset and is not addressed.

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?

There is a single required parameter with 100% schema description coverage, including a precise regex pattern and the 'CrossingKey marketplace provider identifier' definition, so the schema carries the full burden. The description adds nothing about providerId, so 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?

The phrase 'Public active provider metadata' identifies the resource and scope (active providers only), which is more informative than the bare tool name. However it never states a retrieval verb and gives no signal distinguishing it from the sibling provider.describe, so an agent cannot tell which of the two to call.

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?

'FREE' tells the agent there is no cost barrier, and the authorization note tells it that pending applications require owner/admin rights, which implicitly routes it toward active providers. But there is no explicit when-to-use versus provider.describe, and no statement of what happens for non-existent IDs.

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