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

Annotations declare readOnlyHint=false, destructiveHint=false, openWorldHint=false, so the write/non-destructive profile is already covered. The description adds nothing beyond confirming creation: no note on secret handling, validation of keys against the exchange, or whether the exchangeId must pre-exist.

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 short sentences, front-loaded with the action and followed by the endpoint path. No waste, though brevity here edges into under-specification rather than tightness.

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 mutation tool with no output schema and a nested required body containing credentials, the description omits the return shape, error behavior, and security-relevant context. Annotations cover only the safety profile, leaving meaningful gaps.

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?

The single body parameter is a nested object whose required fields publicKey and privateKey have no description in either the schema or the description. The description says nothing about parameter shape, formats, or which exchanges accept 'extra', so it fails to compensate for the reported 0% top-level coverage.

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?

Clear specific verb+resource: 'Create a new exchange API key', which distinguishes it from the get_api_exchange and delete_api_exchange_id siblings. It does not, however, explicitly differentiate from post_api_exchange_test, which is the closest alternative an agent must choose between.

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?

No when-to-use guidance, no prerequisites, and no mention of the sibling post_api_exchange_test (which presumably creates a test key). The agent must infer the choice from the name alone.

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