ebay_get_signing_key

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

With no annotations provided, the description alone carries the burden. It frankly states that the private key is not stored by eBay, which is a key behavioral trait. However, it does not disclose other potential behaviors like required permissions, rate limits, or side effects. The description is honest but minimal.

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?

The description is very concise at one sentence. It is front-loaded and contains no unnecessary words. While it could benefit from additional structure (e.g., listing return fields), it is efficient for a simple GET operation.

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?

Given the tool's low complexity (1 required parameter, no output schema), the description provides adequate information: what it does, what it returns, and a notable absence. It lacks error condition details but is largely complete for typical use. A simple tool does not require extensive documentation.

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 schema already describes the single parameter 'signingKeyId' as 'The system-generated eBay ID of the signing key', achieving 100% coverage. The description does not add additional meaning beyond referencing 'by ID', so it provides no extra value, baseline 3.

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 description clearly states the verb 'Get', the resource 'signing key', and the method 'by ID'. It also specifies what is returned ('public key and metadata') and explicitly notes what is not returned ('private key is not stored'). This distinguishes it from sibling 'ebay_get_signing_keys' which lists all keys.

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?

The description does not explicitly provide when-to-use or when-not-to-use guidance. It implies usage for retrieving a specific signing key by ID, but does not contrast with 'ebay_get_signing_keys' or mention prerequisites like authentication. The information about the private key not being stored is a subtle hint but not a clear usage guideline.

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