> ## Documentation Index
> Fetch the complete documentation index at: https://docs.adcontextprotocol.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Sell-side governance boundaries

> How seller acceptance, buyer spend authority, negotiated change rights, and seller-internal review remain distinct in AdCP.

AdCP governance is intentionally asymmetric. A buyer agent spends money on
behalf of a principal, so it needs authority from that principal. A seller does
not need authority from the buyer to decide whether it will accept a campaign,
creative, or change. The seller instead acts under its own commercial,
operational, and legal policies.

This is a split-authority model, not a missing seller-side approval layer.

## Keep the authority layers separate

| Layer                    | Question it answers                                                              | Protocol surface                                                                                                         |
| ------------------------ | -------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ |
| Buyer governance         | May this caller commit or change spend for the buyer?                            | [`check_governance`](/dist/docs/3.2.0-beta.9/governance/campaign/tasks/check_governance) and signed `governance_context` |
| Seller acceptance        | Will this seller accept this business, campaign, creative, targeting, or format? | [Acceptance-policy discovery](/dist/docs/3.2.0-beta.9/media-buy/media-buys/policy-compliance) and structured task errors |
| Negotiated change rights | Which post-acceptance changes did these parties agree the buyer may request?     | `commercial_terms.change_terms[]` and runtime `available_actions[]`                                                      |
| Seller operations        | How does the seller evaluate or fulfill an accepted request?                     | Seller implementation detail                                                                                             |

A successful governance check establishes buyer authority; it does not oblige a
seller to transact. Conversely, a seller's willingness to transact does not
grant a caller permission to spend buyer funds.

## Seller review is internal

A seller may use deterministic rules, an AI system, human review, or any
combination of them to decide whether to accept a request. That workflow does
not need protocol orchestration and does not make the seller a counterpart
governance authority over the buyer's plan.

Buyer-visible timing may still be useful. Proposal-bound change terms can state
that an action is `seller_managed` and provide elapsed-time response and
completion maxima. Those terms describe the service the buyer can rely on; they
do not reveal whether a person reviewed the request or require the buyer to
coordinate the seller's internal queue.

## Rejection is a disposition, not a governance veto

An authorized action can still fail under seller policy. Use the error category
that identifies the actual boundary:

* `POLICY_VIOLATION` when seller content, advertising, legal, or commercial
  policy rejects an otherwise authorized action.
* `ACTION_NOT_ALLOWED` when a media-buy change is outside the accepted terms or
  is not currently available.
* `PERMISSION_DENIED` when the authenticated caller, credential, account scope,
  or signed governance context lacks authority.

When a seller rejects an approved action, the buyer reports the failure through
[`report_plan_outcome`](/dist/docs/3.2.0-beta.9/governance/campaign/tasks/report_plan_outcome)
with `outcome: "failed"`. The governance audit retains the bounded,
buyer-attributed error evidence so an auditor can explain why execution did not
occur. The copied error is an audit record; it neither grants the seller plan
authority nor becomes seller-attested evidence.

## Governance-agent acceptance is dependency management

A seller may declare which governance agents it can depend on and reject an
unacceptable binding during
[`sync_governance`](/dist/docs/3.2.0-beta.9/accounts/tasks/sync_governance). This decision is about
the endpoint the seller must call for authorization and recovery. It does not
allow the seller to modify the buyer's governance rules or approve buyer spend.

Together, these boundaries preserve the central invariant: buyer authority,
seller acceptance, negotiated commercial rights, and seller-internal operations
remain attributable without being collapsed into one jointly controlled
governance agent.