Get credential schema

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

Beyond the annotations (readOnlyHint, idempotentHint, etc.), the description adds valuable behavioral context: it returns a 'validated upstream field contract,' does not touch stored credentials, and requires specific permissions. This helps the agent understand side effects and expectations.

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 and well-structured: it starts with the core purpose, then clarifies key terminology, states limitations, and points to an alternative. Every sentence adds distinct value without redundancy.

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 the simple single-parameter contract and existing output schema, the description is complete. It covers purpose, parameter semantics, usage alternatives, prerequisites, and behavioral constraints, leaving no critical gaps for an agent to invoke the tool 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?

While the schema covers the format of credentialType, the description adds crucial semantic meaning: it clarifies that credentialType is the 'public type name used by create/update, not a stored credential ID, name, or secret.' This prevents common misuse and goes beyond schema-level documentation.

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: 'Get n8n's Public API field contract for one credential type.' It uses a specific verb and resource, and explicitly distinguishes itself from n8n_credentials_get by noting the difference between public type names and stored credential metadata.

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 explicitly tells when to use this tool versus alternatives: 'Use n8n_credentials_get for stored metadata.' It also clarifies what it does not do ('does not read or test a stored credential') and mentions the required 'schema-read permission,' providing clear usage boundaries.

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