set_proxy_credentials

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

With no annotations, the description carries full burden. It discloses that username and password are secrets (1-64 chars), never echo back or log them, and the response does not return them. It mentions the scope requirement and that it's a plain write (not gated). Missing details on idempotency or error handling, but sufficient for a credential setter.

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 concise (3 sentences) and front-loaded with the core purpose. Every sentence adds value: scope, secret handling, sibling tool reference. No redundant information.

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?

Given no output schema or annotations, the description covers all essential aspects: purpose, scope, parameter secrets, constraints, and relationship to sibling tool. It is complete for a credential-setting tool.

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% with parameter descriptions, but the description adds context: secrets, never echoed/logged, 1-64 char constraints, and id from list_proxies. This improves the agent's understanding beyond the schema alone.

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 explicitly states 'Set a proxy service's username/password credentials', using a specific verb and resource. It also specifies 'ISP proxy services only' and distinguishes from sibling set_proxy_auth_method, which sets the auth method itself.

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 provides clear when-to-use guidance, including scope requirement (services:write), a note that proxy writes share scope with VM/k8s mutations, and an explicit alternative (set_proxy_auth_method) for flipping the auth method. It also mentions that id comes from list_proxies.

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