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

Annotations only declare the generic profile (write, non-idempotent, non-destructive, closed-world). The description adds real behavioral context beyond that: nothing is persisted until the link is first opened, and the link functions as a secret key that must be handed over once and never publicized. It does not, however, warn about the consequence of calling it twice (idempotentHint=false), which is the one mutation risk an agent might hit.

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?

Four short clauses, resource stated first, then precondition, then behavior, then the secrecy warning. The colon-chained style is idiosyncratic but no sentence is wasted.

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 one-parameter creation tool with no output schema, the agent needs to know what it gets back and how to treat it; the description supplies both (the private link, treated as a key it must deliver and keep private). Only the repeated-call behavior is left unstated.

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 coverage is 100% and the single parameter is already described, so the schema suffices. The description reinforces the parameter's intent with the consent framing ('Only after the person said yes'), adding ethical meaning rather than duplicating the schema.

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 names a specific resource (a new, empty FactoGraph store with its own private link) and clarifies that this link is what other tools accept as `store`. The creating verb is only implied by the title 'Make a store for the person' rather than stated outright, but the outcome is unambiguous. No sibling tool (ask, getManual, getStep, listFacts, replyToPrompt, startStep) overlaps with it, so differentiation is not an issue.

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?

An explicit precondition is given: 'Only after the person said yes to having one,' which matches the required `person_agreed` gate. It does not name alternatives, but none exist among the siblings, so there is little else to route to.

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