call_service

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

With no annotations, the description carries the full burden of behavioral disclosure. It explains the security model: the credential is fetched from Clavis vault and injected server-side, so the raw API key never enters the conversation. It also states that this prevents exfiltration, adding meaningful 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 three sentences long, each serving a distinct purpose: stating the action, explaining the credential handling, and providing usage guidance. It is front-loaded with 'RECOMMENDED' and wastes no words.

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?

The description covers the tool's purpose, security behavior, and preferred usage, while the schema exhaustively documents parameters. Although there is no output schema and the description doesn't explicitly state the return format, the tool is an API caller so the response is presumably the upstream response; this is a minor gap given the overall context.

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%, so the schema fully documents each parameter. The description reinforces the purpose of service_name (credential injection) but doesn't add new parameter-level details beyond what the schema already provides, earning the baseline score.

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 clearly states the tool's function: 'Make an API call with server-side credential injection.' It names the specific resource (Clavis vault credentials) and distinguishes itself from sibling tool get_credentials, so there is no ambiguity about what this tool does.

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?

Explicit guidance is provided: 'Prefer this over get_credentials' with a rationale that it eliminates prompt-injection exfiltration. The 'RECOMMENDED' label further signals preferred usage over the alternative.

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