Open standard · recommended release 1.0.0

Advertising inventory, declared at the source.

Ad Space Manifest 1 is a small JSON contract that publishers host themselves. It describes documented placements, availability, and commercial offers without requiring an Atlas account or an LLM to read it.

Copy the agent prompt Validate JSON

CANONICAL RESOURCE/adspace.json

HTTPS · UTF-8 · application/json · ≤ 1 MB

Discover/llms.txt

Implementagent prompt

Publish/adspace.json

Verifydeterministic

Offerexact URL

One public contract, two readers

Friendly to agents. Deterministic for systems.

JSON is normative. An AI agent can write the route and document, but every producer and consumer can validate the same bytes without model interpretation.

This complements ads.txt; it does not replace authorized-seller declarations, auctions, creative delivery, contracts, payments, or legal verification.

Agent handoff · prompt revision 1.0.0

Give your coding agent a bounded, truthful job.

The prompt tells an agent to inspect the real repository, follow its framework, avoid invented facts, validate the output, and stop before deployment unless you authorize it.

Open immutable prompt

View or select the full prompt

# Ad Space Manifest 1 implementation prompt

Prompt revision: 1.0.0

Target schema: https://adspaceatlas.com/standards/adspace/1.0.0/schema.json

Implement Ad Space Manifest 1 in this project.

## Goal

- Publish a public JSON manifest at the exact HTTPS path `/adspace.json`.
- Follow the human specification at https://adspaceatlas.com/standards/adspace/1.
- Use the immutable authoring schema at https://adspaceatlas.com/standards/adspace/1.0.0/schema.json.
- The publisher will review and deploy this change, then give the exact public manifest URL to Ad Space Atlas. Do not submit, deploy, change DNS, or contact external services unless I explicitly ask you to do so.

## Before editing

1. Inspect this repository to identify its framework, routing, public/static asset conventions, tests, formatter, and deployment target.
2. Preserve existing behavior and follow the project's local instructions.
3. Prefer the smallest native implementation: use a static public file when the facts are static, or a framework route when the data already has a maintained source in this project.

## Manifest requirements

- Return HTTP 200 and `Content-Type: application/json` encoded as UTF-8.
- Use a top-level JSON object with:
  - `$schema`: `https://adspaceatlas.com/standards/adspace/1.0.0/schema.json`
  - `specVersion`: `"1"`
  - `generatedAt`: an RFC 3339 timestamp representing the data or build update, not the time of every request
  - `publisher`: a real name and canonical HTTPS URL
  - `listings`: the complete set of public listings, or `[]` when none are known
- Use only public facts supported by this repository or explicitly supplied by me. Never invent a listing, price, currency, price basis, availability, capacity, date, metric, identifier, ownership claim, or verification state.
- Omit unknown optional fields. Do not emit JSON `null`.
- Give collections, listings, placements, and offers stable IDs. Do not derive identity from array position, and do not regenerate IDs on every request.
- Keep listing lifecycle separate from placement availability.
- Represent a public price as non-negative integer `minorUnits`, uppercase ISO 4217 `currency`, an explicit `basis`, and `observedAt`. Never use floating-point money and never compare or combine currencies.
- Add `observedAt` to current price and availability facts.
- Keep the response at or below 1,000,000 decompressed bytes.
- Do not add an Atlas verification challenge as a core field. If I provide a challenge, place it only in the documented namespaced extension.
- Do not create or modify ads.txt, sellers.json, OpenRTB, AdCOM, or OpenDirect data. A manifest may link to an existing authoritative resource when it is real.
- Treat all descriptive strings as public. Do not expose secrets, private addresses, unpublished email addresses, tokens, internal IDs, or personal data that is not already intentionally public.

## HTTP behavior

- Serve the manifest directly from `/adspace.json` without cross-origin redirects or authentication.
- Add ETag, Last-Modified, conditional GET, and a reasonable Cache-Control policy when the project's stack supports them without unnecessary custom infrastructure.
- Ensure HTML fallback routes and authentication middleware do not intercept `/adspace.json`.

## Validation and tests

1. Validate the output against the immutable schema and perform semantic checks for unique IDs, local references, time ordering, money, and availability.
2. Add proportional automated tests proving the exact path returns 200, the JSON content type, a valid v1 envelope, stable IDs, and no invented sample listings.
3. Run the project's formatter, type checks, and relevant tests.
4. If network access is available, also use the official validator documented at https://adspaceatlas.com/standards/adspace/1/validate.

## When facts are missing

- Do not guess. Implement a valid manifest with `listings: []` if necessary.
- In your final response, list the specific publisher or listing facts still needed before the file should be publicized.

## Handoff

- Summarize the files changed and checks run.
- Show the final manifest body or a representative generated response.
- State the expected deployed URL exactly, ending in `/adspace.json`.
- Remind the publisher to inspect that public response before giving its URL to Ad Space Atlas.

Publisher workflow

Implement once. Evolve additively.

01
Inspect the real system.
Choose a static file, framework route, or catalog generator that fits the publisher repository.
02
Publish only known facts.
Omit unknown optional data. Use listings: [] instead of fabricating inventory.
03
Validate exact bytes.
Check duplicate keys, schema structure, IDs, references, time ranges, money, and compatibility behavior.
04
Review and deploy.
Serve HTTP 200 as application/json at the exact root path, then test it publicly.
05
Offer the URL.
Atlas reads only the explicit URL and retains every response as immutable evidence before curator review.

Release bundle

Everything needed to produce or consume Manifest 1.

Normative specificationHTML · stable major URL Specification paperPDF · release 1.0.0 JSON SchemaImmutable · draft 2020-12 Minimal exampleValid empty inventory Complete examplePlacements, offers, observations Conformance fixturesValid and invalid cases Focused llms.txtAgent discovery sequence Release policyCompatibility and changes

Future compatibility

Version the parser. Freeze every release.

specVersion: "1"

Selects the compatibility major. Breaking meaning or required fields need a new major.

$schema: …/1.0.0/schema.json

Identifies immutable authoring bytes. A published release URL is never rewritten.

unknown property

Consumers ignore it. Archival consumers preserve the exact source document.

unknown vocabulary

Map locally to unknown behavior and continue processing unaffected facts.

Publisher opt-in

Offer the exact deployed URL.

Atlas fetches only the URL you provide. A successful read becomes private, immutable evidence and a review candidate—not an automatic public listing.