Find a customer by ID, full name, or phone number, then retrieve their details from the legacy CRM system.
Find a customer by id, name, or phone number
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | Full name of the customer | |
| phone | No | Phone number of the customer | |
| customer_id | No | MongoDB ObjectId of the customer |
| Name | Required | Description | Default |
|---|---|---|---|
| customer | Yes |
Changes observed during successful MCP inspections.
v0.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Without annotations, the description carries the burden of behavioral disclosure. 'Find' reasonably implies a read-only operation with no modification side effects, which is helpful. However, it does not clarify behavior when no parameters are passed, when multiple parameters are passed, or when no matching customer exists.
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 entire guidance is one efficient sentence with no filler. The action and the target identification method are immediately evident, making it easy to scan and parse.
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 simple lookup tool, the description conveys the essence, and the output schema covers return structure. Yet all three input parameters are optional, and the description never states that at least one should be provided or how multiple identifiers interact, leaving an important call-time gap.
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%, so the baseline is 3. The description adds marginal value by framing the three properties as alternative search identifiers, but it does not explain whether they are mutually exclusive, combinable, or required, so it does not substantially improve on the schema.
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 uses the specific verb 'find' and identifies the resource 'customer' plus the three lookup keys (id, name, phone). This clearly separates it from siblings like list_customers, create_customer, update_customer, and delete_customer.
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 phrase 'by id, name, or phone number' implies when it should be used: when you have a customer identifier and need that customer's record. It gives clear context but stops short of explicitly contrasting with list_customers or noting exclusions, so it does not reach the top tier.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.