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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is fully covered elsewhere. The description contributes the content scope of the result, which matters because there is no output schema. It does not disclose how 'recent' is bounded, whether any sections can be empty or truncated, or whether extra permissions are needed.

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?

One sentence, front-loaded with the lookup semantics and then the returned sections. No filler, no restatement of the title.

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 tool with rich annotations and no output schema, the description covers what the agent gets back, which is the main gap the structured fields leave. The remaining shortfall is the lack of differentiation from the other customer-context tools in the sibling set.

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 parameter is documented as 'Customer id, as returned by the customer list or customer search'. The description adds only the association between customerId and a full-detail lookup, which is the baseline for a one-parameter tool.

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 ('Full details of one customer'), keys it on customerId, and enumerates the payload (contact data, notes, recent quotes, projects, totals). It does not distinguish itself from the sibling fetchCustomerContext, so an agent cannot tell from the description alone which one to pick.

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: it requires a single customerId, which suggests 'call this when you already have an id' as opposed to the list/search flows implied by fetchCustomersContext. There are no explicit when-to-use or when-not-to-use statements, and no pointer to alternatives.

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