dex_update_custom_field

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states this is an update operation, implying mutation, but doesn't describe what happens during updates (e.g., whether changes affect existing data, if it's reversible, permission requirements, or error conditions). The example 'rename it' suggests one behavioral aspect but leaves others undocumented.

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 brief and front-loaded with the core purpose. The parenthetical example adds some context without unnecessary elaboration. However, it could be more structured by explicitly separating the action from the example.

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 complexity (mutation operation with nested parameters, no annotations, no output schema, and 0% schema coverage), the description is inadequate. It doesn't explain what the tool returns, error handling, or the full scope of updatable fields beyond the naming example. For a mutation tool with undocumented parameters, more comprehensive guidance is needed.

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 must compensate for undocumented parameters. It mentions updating 'by ID' which maps to 'customFieldId', and the example 'rename it' hints at the 'name' property within 'custom_field'. However, it doesn't explain the 'type' property or the structure of the 'custom_field' object, leaving significant gaps in parameter understanding.

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 action ('Update') and resource ('custom field definition'), and specifies it's done by ID. It distinguishes from sibling 'dex_create_custom_field' by focusing on updates rather than creation. However, it doesn't explicitly differentiate from other update tools like 'dex_update_contact' or 'dex_update_group' beyond the resource type.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing custom field ID), when not to use it, or how it compares to other update operations in the sibling list. The example 'e.g. rename it' hints at one use case but doesn't establish clear boundaries.

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