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

With no annotations, the description carries the full burden. It discloses that the tool returns a link and a short message, that the page asks for no password and no bank details (reassuring safety), and that the owner writes rules in their own words. It doesn't mention rate limits or whether the link expires, but the key behavioral traits are covered.

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 concise and front-loaded: it states the primary action first, then explains the flow and the return value. Every sentence adds value, and there's no fluff. It's appropriately sized for a tool with no parameters.

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 parameters, no output schema, and no annotations, the description covers the essential context: what the tool does, what the owner does, what the agent receives, and a safety note. It could mention whether the link expires or if there's a follow-up step, but for a simple link-generation tool, this is nearly complete.

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 input schema has zero parameters, so the description doesn't need to explain parameters. The baseline for 0 params is 4, and the description adds context about what the tool does with no inputs, which is sufficient. No parameter documentation is needed.

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 tool's purpose: generating a link to send to the owner/principal so they can set spending rules. It uses a specific verb ('Get a link'), identifies the resource (the person or business that runs you), and explains the outcome (Focxle checks deals and payments against those rules). This distinguishes it from sibling tools like agreement_get or negotiation_open, which serve different purposes.

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 when to use this tool: when you need to invite the owner to define purchasing rules. It doesn't explicitly name alternatives or state when not to use it, but the context is clear enough given the sibling list. A slight gap is the lack of explicit exclusion (e.g., 'use this instead of X when...'), but the purpose is specific enough that an agent can infer the right context.

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