value_update

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

With no annotations provided, the description correctly states 'Only provided fields are changed,' which implies a partial, non-destructive update. However, it does not disclose how array fields (tags, witnesses, etc.) are handled—whether they are replaced wholesale or merged. It also omits side effects like permission requirements or error conditions, leaving notable behavioral gaps for a tool with 12 parameters.

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 exceptionally concise—two sentences, each earning its place. The first sentence states the core purpose, the second adds critical behavioral detail ('Only provided fields are changed'), and the third provides an explicit alternative. There is zero fluff or redundancy.

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 (12 parameters, no annotations, multiple siblings), the description covers the basic update semantics and one sibling, but fails to explain array field behavior, required fields beyond the schema, or the output structure (though an output schema exists). It is minimally adequate but not thorough for a tool with this many parameter choices.

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 description coverage is 0%, yet the description adds no parameter-level information beyond 'fields.' Although parameter names like 'body', 'kind', 'source', and 'status' are somewhat self-explanatory, the description does not elaborate on allowed values, formatting, or the specific intent of each field. For a tool with 12 parameters, this lack of semantic elaboration hinders correct invocation.

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 verb 'Update' and resource 'a value's fields', with the specific behavioral detail 'Only provided fields are changed.' It also directly distinguishes from the sibling tool 'value_retract' by explicitly directing agents to prefer that tool for retraction, which eliminates ambiguity.

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 clear context: use it when you want to modify specific fields on an existing value. It explicitly directs agents to 'prefer value_retract' for retracting with a cause, offering a concrete alternative. However, it does not address when not to use it relative to other siblings like value_add (for creation) or value_drop (for deletion), which would strengthen guidance.

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