# Human functions

URL: /products/service/human-functions · Id: `page:products/service/human-functions`

> People enter a Service as Functions that do a step, as credentialed signers the law requires, or as watchers who direct the work.

A [Human](/business/nouns/human) enters a [Service](/business/nouns/service) in one of three places: doing a step, signing what the law reserves, or directing the business. Each is recorded, graded, and replaceable without changing the promise to the [Customer](/business/nouns/customer).

## One Verb, four kinds of Function
Every step of a Service is a [Verb](/business/nouns/verb), and a [Function](/business/nouns/function) says how it runs. The caller sends the same input and gets the same [Action](/business/nouns/action) back whichever kind runs it.

Take a [Startup](/business/nouns/startup) that prepares annual tax returns for freelancers. Its delivery line uses all four kinds.

| Kind | Runs as | Tax return example |
| --- | --- | --- |
| `code` | Deterministic code | Total income from the connected payment accounts |
| `generative` | One model call | Classify each expense receipt |
| `agentic` | An [Agent](/business/nouns/agent) with tools | Find deductions the freelancer missed and ask about each one |
| `human` | A person, through a [Task](/business/nouns/task) | [Review](/business/nouns/review) a return the [Evaluators](/business/nouns/evaluator) flag |

The kind belongs to the definition, not the interface. When the Agent learns to resolve flagged returns, the review step switches from `human` to `agentic`, and no Customer integration changes.

## When a person does the work
A `human` Function creates a Task and assigns it to a qualified [Worker](/business/nouns/worker) by [Credential](/business/nouns/credential), jurisdiction, and load. The person works it in the supplier [App](/business/nouns/app), their [Mailbox](/business/nouns/mailbox), or a [Channel](/business/nouns/channel). Their output passes the same Evaluators as an Agent's.

Workers who take Tasks through a Startup's supply are [Suppliers](/business/nouns/supplier), paid per Task and never seated in a [Role](/business/nouns/role). A person seated in a Role is a team member instead, placed by [Staffing](/workflows/processes/staffing). [Supply](/products/service/supply) covers how Suppliers are recruited, verified, and paid.

Every human step is also data. Its inputs, outputs, and verdicts become the graded cases an Agent is evaluated against before it takes the step over.

## Moving a step from a person to an Agent
Automation advances one Verb at a time, on evidence. Each step climbs three rungs: `assist`, `supervised`, and `full`.

In `assist`, the Agent does the work and a person approves it. In `supervised`, a person reviews only exceptions; in `full`, review is a sample.

A step moves up when the Evaluators agree with the Agent on at least 95% of the Role's sample. It drops back automatically when agreement falls. The tax Startup's review step reached `supervised` after one filing season: a person now sees only returns with foreign income.

## The legal floor
Some Verbs are [Reserved Acts](/business/nouns/reserved-act): the law reserves them to the holder of a named Credential, so their Function is always human. Signing a tax return as a paid preparer, notarizing a document, and giving legal advice are Reserved Acts in many jurisdictions.

A Service declares its floor in one property. `none` means no Reserved Act; `sign` means Agents prepare and a credentialed person signs; `practice` means the credentialed person does the work. A `practice` step never climbs past `assist`.

[Attest work](/workflows/processes/licensed-review/attest-work) routes the Reserved Act to a credentialed person, whose Credential standing is checked fresh at that moment. The result is an [Attestation](/business/nouns/attestation): signed, frozen, and either `performed` or `declined`. A declined Attestation returns the work to delivery; nothing reaches the Customer unsigned.

## Approvals and direction are not Functions
An [Approval](/business/nouns/approval) does no work: it allows or refuses one pending Action that exceeds a [Limit](/business/nouns/limit) or a [Mandate](/business/nouns/mandate). A refund above the issuing Role's bound waits for one. Outside the legal floor and those bounds, no person sits in the critical path.

Direction does no work either. A watcher can [redirect](/business/nouns/action/redirect) or [cancel](/business/nouns/action/cancel) a pending Action inside its delay window; when nobody intervenes, the Action proceeds.

A founder who wants complex returns handled before simple ones records a [Decision](/business/nouns/decision) or changes a [Setting](/business/nouns/setting). Every affected Task is then kept, reordered, or paused, with the reason on record.

## Next
- [Supply](/products/service/supply): recruiting and paying the people who do the work.
- [Licensed review](/workflows/processes/licensed-review): how every Attestation is made.
- [Licensed-human marketplace](/products/templates/licensed-marketplace): a business built on credentialed supply.