Get client by email

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety and side-effect profile. The description adds behavioral value by specifying the exact return content ('settings, inbound, traffic limits'), which helps the agent gauge whether this tool meets its information needs. It does not contradict annotations and provides useful context beyond the schema.

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 description is two sentences, front-loaded with the primary action and returns, then the usage guidance. No redundant phrases or filler. Every word contributes to understanding what the tool does and when to use it.

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 getter with annotations covering safety, the description provides all necessary context: what it returns, the input requirement, and the fallback alternative. It does not mention error handling or pagination, but these are not expected for this simple tool. The description is fully adequate for an agent to call it correctly.

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?

The schema already describes the email parameter as 'Exact client email/identifier,' and the description reiterates the 'exact email' requirement without adding new constraints (e.g., case sensitivity, format). With 100% schema coverage, the description adds little beyond reinforcing the parameter's meaning, so the baseline of 3 is appropriate.

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 verb ('Get') and resource ('full details for a single client'), enumerates the exact fields returned (settings, inbound, traffic limits), and emphasizes the 'exact email' criterion. This clearly distinguishes it from the sibling list_clients (returns a list) and get_client_traffic (traffic only), making the tool's purpose unambiguous.

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 gives explicit when-to-use guidance: 'Use list_clients first if you do not know the exact email.' This tells the agent the condition under which it should select an alternative, thereby clarifying the precise context for this tool. No other exclusions are needed given the simple, single-purpose nature of the tool.

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