n8n: Get credential

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful behavior beyond that: it returns metadata and that listing is unsupported in the Public API. It does not disclose behavior for missing IDs, permission requirements, or whether secrets are ever exposed, leaving real gaps for a credential-related read.

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 short sentences with the core action front-loaded and the constraint second. The "[UNIFIED]" prefix is filler, and the listing caveat, while useful, is tangential to the tool's own operation, but overall there is little waste.

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 two-param tool with zero schema description coverage and no output schema, the description should define both parameters and ideally the return shape. It leaves "site" entirely unexplained and says nothing about what metadata fields come back, which are material omissions for correct invocation.

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 0%, so the description carries the full burden. It explains credential_id implicitly through "by ID", but the required "site" parameter is never mentioned in either the schema or the description, leaving an agent to guess what it accepts.

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?

States a specific verb and resource ("Get credential metadata by ID") and narrows scope with "metadata", which signals it returns credential info rather than secret values. It does not explicitly distinguish itself from the closest sibling n8n_get_credential_schema, so it falls short of the 5 bar.

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 definition implies usage (supply an ID to fetch a single credential) and rules out listing credentials, which is genuinely helpful. However it gives no guidance on when to prefer this over n8n_get_credential_schema or n8n_get_credential's other siblings, so usage is only implied.

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