n8n_update_credential

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

Annotations cover readOnlyHint=false (mutation), openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable context about immediate propagation to workflows, which isn't captured in annotations, enhancing understanding of real-time impact. No contradiction with annotations.

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?

Two concise sentences with zero waste: the first states purpose and usage context, the second explains a critical behavioral effect. It's front-loaded and efficiently structured.

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 mutation tool with rich annotations (e.g., idempotentHint, openWorldHint) and full schema coverage, the description is largely complete. It adds practical usage context and workflow impact, though lacks output details (no output schema provided), slightly limiting completeness.

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 parameters are fully documented in the schema. The description doesn't add extra semantic details about 'id', 'name', or 'data' beyond what the schema provides, meeting the baseline for high coverage.

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 specific action ('Update credential name or authentication data') and resource ('credential'), distinguishing it from siblings like n8n_create_credential (creation) and n8n_delete_credential (deletion). It precisely defines what can be modified.

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?

It explicitly states when to use this tool ('when rotating API keys or changing OAuth tokens') and provides a key behavioral consequence ('Workflows using this credential will use updated auth immediately'), which helps differentiate from alternatives like n8n_create_credential for initial setup.

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