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

Annotations declare readOnlyHint=false and openWorldHint=true, and the description adds genuinely useful context beyond them: exactly which personal data leaves the system (name, contact details, request) and to whom, plus explicit prohibitions on health details, card numbers, ID numbers and passwords. It does not discuss failure behavior, retry/idempotency, or what a successful send returns, which keeps it short of a 5.

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?

Front-loaded with the action and its effect, then the gating precondition, then the field-level constraint — a logical order. The embedded consent quote is lengthy but is required verbatim for the agent to display, so it earns its space.

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 6-parameter, non-idempotent, PII-transmitting mutation with no output schema, the description covers the essential safety story: consent gating and forbidden data types. It omits what happens after the send (confirmation, errors, delivery guarantees), which an agent might want before reporting success to a person.

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 only 50% — slug, email and phone carry no descriptions — yet the description says nothing about slug format or when email vs. phone should be supplied. It only reinforces meaning for consent ('only if they agreed') and constrains details content (no health/card/ID/password data), so it partially but not fully compensates for the coverage gap.

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?

States a specific verb and resource ('sends the person's request to the ONE business they chose') and the resulting effect ('so it can reply to them'). This clearly distinguishes it from the sibling lookup tools (find_businesses, get_business, list_categories), which do not transmit anything.

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?

Gives an explicit precondition: 'Call only after the person has read and agreed to this' followed by the verbatim consent sentence, plus a rule for setting consent=true only when agreement is given. Nothing about when to call is left to inference.

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