Get a customer

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety is covered. The description adds only that the payload is the full record (address, notes, links), which is modest added context; with no output schema, more about return shape or not-found behavior would have helped.

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?

A single short sentence with the key fact ('full customer record') front-loaded and no padding. The trailing ellipsis is informal and slightly undermines precision, but the size is appropriate.

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 one-parameter read tool with full annotation coverage, this is adequate: the agent knows it is a safe, idempotent full-record fetch. It stops short of describing error/not-found handling or the structure of the returned record, which matters since no output schema exists.

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 description coverage is 100% and the single required customerId parameter is documented in the schema, so the baseline is 3. The description adds nothing about the identifier's format or constraints, leaving the schema to do all the work.

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?

States a specific verb and resource (fetch a single customer) and the parenthetical 'address, notes, links…' signals it returns the complete record rather than a summary. It implicitly separates itself from list_customers/find_customers via 'full record', though it never names those siblings.

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?

Usage is only implied: an agent can infer this is the lookup for a single known customerId versus the list/find siblings. There is no explicit when-to-use, no exclusion of find_customers, and no statement of what to do if the ID is unknown.

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