OpenAPI MCP Gateway

Find purchase order by ID.

get_order_by_id

Read-onlyIdempotent

Fetch an order by its ID. Use integer IDs <=5 or >10 to get a valid response; other values trigger exceptions.

Instructions

For valid response try integer IDs with value <= 5 or > 10. Other values will generate exceptions.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "orderId": "<orderId>"
    },
    "name": "get_order_by_id"
  }
}

Input Schema

Name	Required	Description	Default
`orderId`	Yes	ID of order that needs to be fetched

Schema Changelog

Changes observed during successful MCP inspections.

Changed3 schema fields changedv0.6.2Aug 11, 2026
- addedInput schema / properties / orderId / format
```
Added value: +"int64"
```
- removedInput schema / properties / orderId / title
```
Removed value: -"Orderid"
```
- removedInput schema / title
```
Removed value: -"upstream_callableArguments"
```
First observedv1.0.0Jun 11, 2026

TDQS

B3/5.0

Behavior4/5

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

The description discloses that IDs outside the stated ranges generate exceptions, which is a behavioral quirk not captured by the readOnlyHint, openWorldHint, or idempotentHint annotations. It adds useful information about error behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise—a single sentence—and wastes no words. However, it omits the primary purpose, so it is terse but not fully informative.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the title supplies the purpose and the readOnlyHint/idempotentHint cover safety, the description's extra info about exceptions makes the overall definition reasonably complete for a simple fetch-by-ID operation. Still, the description alone would be incomplete without the title and annotations, so it earns a mid score.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema defines orderId as int64 with a generic description. The description adds a specific constraint (IDs <=5 or >10) that affects whether a valid response is returned, providing meaningful semantic detail beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose2/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description does not state what the tool does; it only provides a note about valid ID ranges ('try integer IDs with value <= 5 or > 10'). The title 'Find purchase order by ID' supplies the purpose, but the description itself lacks an explicit verb+resource statement, making it vague and failing to distinguish from siblings like get_pet_by_id without relying on the title.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives no guidance on when to use this tool versus alternatives such as get_pet_by_id or find_pets_by_status. It merely hints at ID values that yield valid responses, which is a parameter constraint, not usage context.

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