orb_get_customer_by_external_idFetch a single customer by your external customer id. Orb API: GET /customers/external_customer_id/{external_customer_id}.
| Name | Required | Description | Default |
|---|---|---|---|
| external_customer_id | Yes | Your external customer id. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so the agent knows this is a read-only operation. The description adds only 'single customer' and the API path but does not disclose behavior for missing IDs, response format, or any other operational details. Adequate given the annotation coverage, but not rich.
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 succinct sentences, with the core purpose front-loaded and the API reference following. Every word contributes; there is no padding or redundancy.
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 single-parameter, read-only lookup tool with readOnlyHint set, the description is largely sufficient. It could mention what happens when the ID does not exist, and since there is no output schema, a hint at the return shape would help, but these are minor gaps for such a simple operation.
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 100% and the schema already defines external_customer_id as 'Your external customer id.' The description repeats this without adding format, constraints, or usage examples, so it stays at the schema-covered baseline.
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 states a specific action ('Fetch a single customer') and resource ('by your external customer id'), clearly distinguishing it from orb_get_customer and orb_list_customers. The API endpoint further confirms the exact operation.
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 implies this tool should be used when the external customer id is available, and sibling names suggest orb_get_customer is for internal Orb IDs. However, it does not explicitly state when not to use this tool or name the alternative, so it stops short of full guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Every tool name clearly specifies a distinct action and resource (e.g., list_subscriptions vs get_subscription). There is no ambiguity between tools as each targets a unique combination of verb and noun.
All tool names follow a consistent pattern: 'orb_<verb>_<resource>' in snake_case. This makes them predictable and easy to distinguish.
With 26 tools, the set covers many resources and operations for a billing platform. While slightly above typical range, each tool justifies its existence given the domain complexity.
The tool surface provides extensive read capabilities and basic customer CRUD, but lacks create/update/delete for most other resources (e.g., subscriptions, invoices) and missing operations like void or cancel. This creates notable gaps for full lifecycle management.