variable_library_update_definition

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

Annotations already indicate this is not read-only and not destructive. The description adds the 'long-running' caveat and specifies the types of files read, which is useful behavioral context beyond the schema. It does not, however, describe side effects, merge/replace behavior, or operation-status handling.

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 a single, front-loaded sentence that communicates the core action, the long-running nature, and the source of definition files with no wasted words. It is appropriately compact while preserving essential details.

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 three-parameter tool with fully documented inputs, this description is largely sufficient: it names the action, the key behavior, and the long-running nature. It could be more complete by noting what the operation returns or how to monitor completion, but the core invocation context is covered.

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 already documented in the schema. The description adds only contextual value by naming the definition file types, but it does not meaningfully expand parameter semantics beyond what the schema provides.

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 states a clear action ('Update a variable library's definition') and identifies the resource, plus the mechanism (reading definition files from a directory). It distinguishes itself from sibling tools like variable_library_get_definition by focusing on updating, though it does not explicitly contrast with variable_library_update.

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 implies usage through 'definition files' and 'long-running,' but it provides no explicit guidance on when to prefer this over variable_library_update or variable_library_get_definition. There are no stated exclusions, prerequisites, or alternative selection criteria.

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