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

With no annotations provided, the description carries full behavioral burden and does it thoroughly. It discloses destructive semantics (omitting a term deletes it), trimming behavior for over-limit inputs, the return of the stored result, and the critical constraint that inferred terms must never be added. This goes well beyond what the raw schema or annotations would convey.

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 but every sentence earns its place. It front-loads the primary purpose and replacement rule, then systematically covers read-before-write, limits, return value, and usage exclusions. Despite its length, there is no filler or redundant restatement of the tool name.

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 tool has no annotations and no output schema, the description fully compensates by covering side effects, edge cases (trimming), return behavior, and policy constraints. It is complete enough for an agent to invoke correctly without needing additional context.

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?

Although the schema already describes the terms array as 'The complete list, in the order the user wants to see it', the description adds crucial constraints: send the WHOLE list, up to 10 terms of 60 characters, trimming rather than refusing, and the empty-array-clears behavior. These details are not in the schema and materially affect how to set the parameter.

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 opens with a specific action: 'Replace the list of things the user says matter most', clearly identifying the resource (the focus list) and the operation (replace). It also distinguishes itself from siblings by emphasizing replacement rather than appending, and by stating 'this replaces, it does not append'.

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?

Explicit guidance is provided: 'Read the current list from get_document first' names the companion tool to use before this one, and 'ONLY call this when the user asks you directly, in conversation. A scheduled run must never touch it' gives a clear when-to-use and when-not-to-use rule. This strongly differentiates from potential alternative uses.

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