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

Beyond the basic safety hints provided in annotations, the description adds critical behavioral context by stating that it 'keeps your values and body' and writes a 'new version.' Furthermore, it clearly limits parameter scope by noting that certain fields are 'not derived fields: those come from hashn.'

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 dense with functional information, yet every clause serves a specific purpose—defining the action, explaining the mechanism (new version), and setting usage rules. It is highly efficient.

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 high schema coverage and the detailed explanations of the write behavior and usage triggers, the description is exceptionally complete. The agent receives all necessary context to select and invoke the tool correctly.

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?

While schema coverage is 100%, the description provides valuable semantic constraints on the 'fields' parameter. It explicitly warns the user about the limitation regarding 'derived fields,' which is a crucial operational rule not fully captured by the schema structure alone.

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 defines the tool's function as updating a listing to its convention by 'writ[ing] the expanded listing... as a new version.' It also references 'expand_listing' as a sibling tool, helping distinguish its specific role.

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?

Usage is explicitly guided: 'Use it when a notice says a convention moved on, or to add what a notice asks for.' This provides direct, actionable criteria for the agent to determine when to use this tool over alternatives.

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