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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety and scope are covered. The description adds genuine value by disclosing the payload contents (result notes, tracking, files), but says nothing about behavior on an unknown id, permissions, or whether the tracking/files sections can be empty. With annotations carrying the safety profile, a 3 fits.

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?

It is short and front-loaded, but it is a single fragment that omits the main verb, so the brevity reads as under-specification rather than efficiency. Nothing in it is wasted, but too little is there.

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 lookup tool with no output schema and an undocumented required parameter, the description should at minimum define the id and how the request/order distinction works. It instead only gestures at return contents, leaving the caller to infer the rest from the schema alone.

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 coverage is only 50%: api_key is documented in-schema, but the sole required parameter, id, has no description anywhere. The description does not clarify what the id identifies (a request, an order, an opaque handle) or its format, so it fails to compensate for the coverage gap.

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 sentence names the resource and its scope ('One order') and enumerates what comes back ('result notes, tracking and files'), which does distinguish a single fetch from the sibling list_requests. However, it is a noun fragment with no verb, and it silently renames the tool's 'request' to 'order', leaving the agent to guess whether those are the same entity.

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?

There is no when-to-use guidance at all: nothing says to prefer this over list_requests, nothing about how to obtain the required id, and no prerequisites or failure conditions. The only implicit signal is the word 'one', which the agent must interpret on its own.

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