a2a2p — Agent-to-Agent-to-Physical
An open protocol for turning intent into physical things.
An AI agent can reason about a bracket. It cannot make one exist. a2a2p is the missing layer: describe what needs to be true about the world, and get back a manufacturable specification, an engineering review grounded in real material properties and real geometry, and a price.
The specification is public domain (CC0) — implement it freely,
including in products competing with this one. a2a2p.com is a reference
implementation, not the protocol.
Abundance arrives as the distance between knowing what is needed and the thing existing collapses toward zero. Today that distance is mostly friction. This is an attempt to remove it.
Try it in 30 seconds
No API key. No signup. No auth.
claude mcp add --transport http a2a2p https://a2a2p.com/mcp
Or any MCP client:
{ "mcpServers": { "a2a2p": { "type": "http", "url": "https://a2a2p.com/mcp" } } }
Client only speaks stdio? Bridge to it:
npx a2a2p-bridge # or: docker run -i --rm ghcr.io/deadlypillow/a2a2p
The bridge is dependency-free and takes A2A2P_ENDPOINT, so it works against
any implementation of the spec, not just this one.
Or plain HTTP:
curl -X POST https://a2a2p.com/api/review \
-H "Content-Type: application/json" \
-d '{"intent":{"purpose":"Outdoor bracket holding a 10kg sensor in direct sun","environment":["outdoor","uv_exposure"],"quantity":20},
"specification":{"process":"fdm_3d_print","material":"pla","tolerance_class":"precision"}}'
You get back, instantly: PLA degrades in UV — specify a UV-stable grade or switch material. As-printed accuracy is ±0.2–0.5 mm; "precision" needs post-machining or a relaxed class. Plus a quote-readiness score and what to add to raise it. Nothing is stored.
Capabilities
| Tool | What it does | Latency |
|---|---|---|
review_specification | Engineering review with auditable beam deflection/stress for explicit load cases, a compact next patch, visible completion path, optional CAD accelerators, and a direct next_call MCP/REST handoff — never invented defaults. | instant, stateless |
get_supply_options | Deterministic price and lead-time estimates today; a future named-provider quote is explicitly distinguished. Attach an STL (measured fully) or a STEP file (envelope, units, machining complexity). | instant |
request_physical_solution | Full decision-support resolution: recommended path, buy-vs-make, and delivery risks. Returns immediately with the review embedded. | sub-second |
revise_requirement | Apply a sparse clarification patch to a prior request without losing its decision trail. Creates an immutable linked revision with a deterministic before/after readiness comparison; supports retry idempotency. | sub-second |
check_request_status | Retrieve the resolution report and any persisted revision-readiness feedback. | instant |
Also served: /spec · /conformance · /policy · /api/providers · /llms.txt · /schema
The idea worth stealing
A physical requirement has two layers, and conflating them is the main reason manufacturing communication fails:
- Intent — what must be true about the world. "Holds 15 kg, outdoors, ten years."
- Specification — what object satisfies that. "6061-T6, 4 mm, anodized."
Most systems demand the second and discard the first. Then, downstream, someone proposes a substitution and nobody knows what the part was for. a2a2p accepts intent alone as a complete request — deriving the specification is the protocol's central act of value — and carries the intent forward permanently.
Two rules in the spec are normative, and they are worth adopting even if you use none of this code:
- An estimate MUST NOT be presented as a quote (§5.2.1). An agent that cannot tell a computed guess from a commitment will eventually commit real money to a fiction.
- Anything that fabricates MUST screen requests and publish its policy (§5.5). Silent refusal is non-conformant — an agent that cannot learn why it was refused cannot correct course.
Conformance
L1 Speaks → L2 Prices → L3 Resolves → L4 Fabricates. Self-declared;
there is deliberately no certifying authority.
Verify any implementation yourself — the suite ships with the spec:
node tests/conformance.mjs https://a2a2p.com # or your own endpoint
41 assertions, each citing the spec section it enforces. It deliberately cannot prove fabrication (that would mean placing real orders), so it verifies the L4 prerequisites and records the fulfilment claim as unproven — otherwise any implementation could publish a policy, make nothing, and pass as L4.
This implementation declares L3 and publishes exactly where it falls short at
/conformance — including that L4 is unmet,
that STEP files yield envelope and complexity but not solid volume, and that deterministic screening
cannot read intent. An implementation that will not hold itself to its own spec
has written a brochure.
Honest status
Built deliberately ahead of demand. As of July 2026:
- ✅ Assessment, bounded beam physics, pricing, geometry measurement, screening, and resolution reports are live and free.
- ⚠️ No fulfillment path is active. The implementation is L3: it does not route supplier RFQs, auctions, payment, orders, or fabrication. Any L4 activation must meet the evidence gate in docs/FULFILLMENT_ACTIVATION.md.
- 📐 STL meshes are measured fully (volume, area, complexity). STEP files yield envelope, declared units, and feature-based machining complexity; solid volume needs a B-rep kernel and is reported as unknown rather than guessed.
If you are a manufacturer with a programmatic quoting API, or building one: hello@a2a2p.com. That is the bottleneck for everyone in this space, not just for us.
Repository
SPEC.md the specification (CC0) — the actual product
src/worker.js reference implementation (Cloudflare Worker)
src/schema.js canonical requirement schema
src/review.js deterministic engineering review engine
src/mechanics.js bounded beam deflection/stress sanity checks
src/geometry.js STL mesh measurement (volume, area, complexity)
src/step.js STEP entity-graph parsing (envelope, units, features)
src/supply.js provider adapters + parametric estimator
src/screening.js intake screening (the governance rail)
src/file-inspection.js declared-vs-actual CAD format and bounded metadata checks
src/telemetry.js demand instrumentation
bridge/index.js stdio <-> Streamable HTTP bridge (dependency-free)
Dockerfile runs the bridge; for clients and registries that run servers
tests/test-worker.mjs regression suite
tests/calibration.mjs pricing model vs real published prices
tests/conformance.mjs spec conformance suite — runs against ANY implementation
docs/ research, listings kit, activation gate
PROTOCOL_LOG.md build log — every session, decision, and failure
Run the tests: node tests/test-worker.mjs · Deploy: npx wrangler deploy
Contributing
Implementations of the spec, conformance reports, corrections, and competing implementations are all welcome — that is what a standard is for. Issues and PRs here, or hello@a2a2p.com.
Licensing, in two parts (see LICENSE):
- Specification (
SPEC.md) — CC0 1.0, public domain. Implement it freely, including in competing products, without permission or attribution. - Implementation (everything else) — MIT.
a2a2p — when agents need things to exist.