get_custom_fieldRetrieve a custom field's details by its ID to view or verify metadata in Paperless-NGX.
Fetch a custom field by ID.
| Name | Required | Description | Default |
|---|---|---|---|
| field_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | ||
| name | Yes | ||
| data_type | Yes | ||
| extra_data | No |
Changes observed during successful MCP inspections.
v1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds no behavioral context beyond restating the fetch action, so it provides no extra transparency beyond what annotations already offer.
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?
A single 7-word sentence contains exactly the necessary information, front-loading the action and object. No wasted 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?
For a one-parameter read tool with output schema and safety annotations, the description is largely sufficient. However, it does not explicitly state that the field must already exist or how it relates to list_custom_fields, leaving minor completeness gaps.
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?
The schema has a single integer field_id with no description (0% coverage). The description's 'by ID' clarifies that field_id is the unique identifier of the custom field, adding essential meaning the schema lacks.
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 'Fetch a custom field by ID' uses a specific verb, resource, and identifier, clearly distinguishing it from sibling CRUD tools like list_custom_fields, create_custom_field, etc.
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?
No explicit guidance on when to use this tool versus list_custom_fields or other alternatives. The usage is implied by the name and 'by ID', but there is no mention of when to prefer this over enumeration or other getters.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.