Brief Completeness Rubric: What AdCP and AAMP Can Actually Read

Score a brief on two axes before you send it anywhere. Transactable tells you whether the receiving side can book from it. Expressive tells you how much of it arrives as structured fields instead of prose. Score each axis separately: a brief can be transactable and still fill almost none of the structured fields.

Transactable is a pass or a fail, and there are two of them because there are two receivers. Score against the receiver you have.

• Transactable (AAMP). The eight fields IAB Tech Lab’s reference buyer agent refuses to construct a campaign without. AAMP is a reference pair of buyer and seller agents rather than a released standard, so its constraints are one vendor’s defaults.
• Transactable (AdCP). The three fields on create_media_buy that a brief author can supply: brand, start_time, end_time. That call requires five, but idempotency_key and account come from your session and your client, not from anything a planner writes. At discovery, AdCP requires buying_mode and nothing else.

A buyer transacting only over AdCP never runs AAMP’s Python validator, so a failure against it is not a failure against the wire.

Expressive is a count out of thirty. AdCP 3.1.13’s product-filters.json declares 30 filter fields. Denominator: all 30 properties, deprecated and ext included. The generator scores against the same 30.

Label every value: stated, derived, assumed, missing

Each of the twenty brief items in the crosswalk gets one of four labels, and the label is part of the artefact.

• Stated. The buyer wrote it. Quote the span. “Budget: $500,000 net” produces total_budget: 500000 with the sentence attached.
• Derived. Unambiguously implied by something stated, with the derivation shown. “$500,000 net” plus a US market gives currency: USD. “November 1 - December 31, 2026” gives both flight dates. Write the derivation on one line. If it needs more than one line, label the value assumed.
• Assumed. The tool picked a value, so it starts off and it renders differently from everything else.
• Missing. Name the field, then name what happens without it.

The labels are for your side, not the seller’s. Neither protocol carries them: on AAMP the brief never leaves the buyer agent, and get-products-request.json has no provenance channel anywhere in it. The only thing that travels is what you type into the brief string, so “channel split: not specified” is a sentence a seller might read and might not. The distinction exists in exactly one place, the accept step in your own agent: an assumed value stays out of the payload until someone accepts it explicitly.

Five checks against your last brief

1. Mark each of the twenty items in the crosswalk stated, derived, assumed or missing, strictly on derived. This is the input to both scores.
2. Count the eight AAMP-enforced fields, plus a budget_pct on every channel, plus brand, start_time and end_time for create_media_buy. All present is transactable. One gap is a brief that can’t become a campaign record, and there’s no partial credit.
3. Count how many of AdCP’s 30 filters you can fill from stated and derived values. That is your expressive score.
4. Find every number in the brief that no planner ever said out loud. Channel splits and attribution windows are where they hide. Report that count next to both scores: an invented split raises transactable, an invented CTR floor raises expressive, and nobody signed either one.
5. Check your KPI against the enums. A planner on r/programmatic described a full-funnel brief whose KPIs were Cost-per-Engaged-Visit and Engaged Visit Rate; AdCP’s 36-value metric list has engagements and engagement_rate, and AAMP’s seven-value list has neither. If your KPI is not in the enum, decide now what it degrades to, because otherwise the seller decides. A goal with no objective field may still have a metric field: incremental_sales_lift is one of the 36 in enums/available-metric.json.

Run the five checks on this brief:

Q4 holiday campaign for a CPG snack brand. Channels: CTV plus digital display and online video. Budget: $500,000 net. Market: United States. Target demo: adults 25-54. Flight: November 1 - December 31, 2026. Goal: drive incremental household penetration and retail sales lift. Requirements: premium CTV inventory, brand safety controls, frequency cap 3 per week.

Transactable: no, against either receiver. The advertiser is “a CPG snack brand”, so advertiser_id is absent on the AAMP side and brand.domain is absent on the AdCP side. There is no campaign name. Three channels are named with no percentage on any of them, so ChannelAllocation can’t construct and the sum-to-100 check never gets to run.

Expressive: six of thirty. channels, budget_range, pricing_currencies, countries, start_date, end_date.

Assumed: two, both AAMP defaults. EVEN pacing, and human approval on plan review and booking. Nothing in the brief itself is invented.

Ten of the twenty rows come back missing: advertiser identity, agency, campaign name, channel budget split, audience segments, KPIs, brand safety, formats, seller preferences and deal type. The stated goal, incremental household penetration and retail sales lift, matches none of AAMP’s four objectives, and AdCP has no objective field at discovery to fail against.

Fill those gaps rather than marking them and the arithmetic still passes. A fabricated 60/25/15 split across CTV, online video and display clears AAMP’s validator: it sums to 100 inside the 0.01 tolerance, no channel type repeats, budget_amount computes off each percentage, and the buyer agent writes a campaign record in DRAFT. The validator checks arithmetic only. A fabricated split that sums to 100 passes. A missing split does not.

Where every part of a brief lands

Twenty things a real brief contains, and where each one goes, plus a last row for everything with no home on either side. AdCP splits them across two calls and three places, get_products at discovery, then create_media_buy and its nested packages[] at execution. AAMP holds them in one Python class inside the buyer agent, CampaignBrief, which never crosses the wire to a seller. A blank in the AdCP or AAMP column means the concept has no home on that side.

The budget split is the row where the two stacks disagree about whose job it is. AAMP puts it in the buyer’s brief and validates it there. AdCP puts it in the seller’s answer: issue #843 reported a Swiss buyer’s brief reading “50% desktop / 20% mobile / 30% in-app, language splits: 40% German / 60% French” with no way for the publisher to respond with a line-item plan, and 3.1 answers it with proposals[], whose allocations are across products and must also sum to 100. So write the split into your brief prose, then read it back off the proposal. Ask for brief_alignment too, a 2,000-character field where the seller explains what it made of what you sent, and the only structured place a seller tells you how it read your brief.

The target demographic has no dedicated field on either side. There is no age or gender filter in product-filters.json, and targeting.age_restriction is for legal compliance on alcohol and gambling, not for planning. “Adults 25-54” is prose in AdCP, and in AAMP it goes inside an open audience-plan object that the buyer agent passes through without a demographic schema of its own. Brief string or filters has the full list of requirements with no typed home.

What AAMP won’t book without

models/campaign_brief.py enforces eight fields, and three cross-field checks on top of them.

Plan against those eight. The module docstring lists nine, adding target_audience[], and the field declaration below it defaults to None, so a consumer that trusts the docstring will expect an audience the code never demands. Two further validators fire only when target_audience is present: validate_content_taxonomy_version raises ContentTaxonomyMigrationRequired on any contextual audience reference from before Content Taxonomy 3.0, and validate_no_global_agentic raises GlobalAgenticUnsupported on a GLOBAL-scoped agentic reference. With no audience neither runs, and the null plan is read downstream as no targeting.

Everything past those eight is optional and defaulted. Omit pacing_model and AAMP applies EVEN.

Nothing re-checks the eight fields after that first validation. The booking flow holds the brief as campaign_brief: dict[str, Any] on BookingState, an untyped dictionary in a second module carrying its own incompatible CampaignBrief.

What get_products requires

Send a get_products request and the only thing that has to be in it is buying_mode. That is the whole required array in get-products-request.json. The brief property is {"type": "string"} with no minimum length and no structure; its description says it is required when buying_mode is brief and must not be provided otherwise, and the schema enforces neither of those sentences. additionalProperties is true on both the request and the filter object, so misspell a filter name and your request still validates, with no seller obliged to notice. The brief-versus-filters placement rules cover the rest, including filter-not-fail: a threshold that lands in required_metrics or required_performance_standards deletes products instead of flagging them, with no explanation of which constraint emptied the array.

No conformance test covers whether a seller read your brief. Issue #2902 asks AdCP’s compliance storyboards to start testing that filters actually filter, because today “an endpoint can accept start_date/end_date, return a correctly-shaped response, pass all compliance checks — and silently return the same data regardless of what dates were passed”. So read the returned products back against the constraints you sent, and keep the mismatches for your next call with that seller. Probe more than one seller before you conclude anything: three registered sales agents return products to an anonymous get_products call, Cora AI, Equativ and No Fluff Advisory, and the registry, measured has the endpoint-by-endpoint result.

Issue #5278 lays out the choice when no structured field exists: know the seller’s format IDs in advance, which breaks cross-seller discovery; accept whatever the seller maps you to; or use the brief string, which its author calls “non-deterministic across sellers”. Issue #5754 found a brief line reading Budget Type: Affiliate / Commission: 4% with no AdCP pricing option to map to, handled out of band instead.

On the AAMP side the brief does not travel at all. ProductAvailsSearch requires productids, accountid, advertiserbrandid and both dates; QuoteRequest requires idempotency_key, product_id and deal_type. Both start from products the buyer already chose. The seller agent’s only reference to a brief anywhere in its source is a comment in models/ucp.py marking three fields on the seller’s audience plan as “requirements from campaign brief”: target_demographics, an untyped dict[str, Any], and target_interests and target_behaviors, both bare list[str]. That comment is the whole of the seller’s brief interface, a note above the fields where brief-derived targeting is expected to arrive, with no schema saying what it looks like.

Where to go next

• Paste a brief into the generator and read the two scores off the same twenty rows, with every value labelled.
• Brief string or filters covers which requirements belong in filters and which belong in the prose.
• The two brief formats, field by field is where the second, incompatible CampaignBrief in the same repository is laid out.