API overview

Generated by npm run next through configure { kind: 'api' } on 2026-10-25: what this tree serves, as platform.claude.com's overview is for the Claude API — one endpoint and every surface around it, read from the handler and the Worker, never written by hand.

Version 1.4.0 · https://qpu.uuidna.com · https://qpu.psg.bg · https://qpu.ceci.workers.dev

Architecture

Everything goes through one MCP endpoint: POST /mcp takes JSON-RPC 2.0 (initialize, tools/list, tools/call); every tools/call result is a block addressed by its content, and every other surface serves or carries blocks. No hardware, no network inside the tools, nothing factored beyond N ≤ 21.

Endpoints

Method	Path	Takes	Answers	Authorization
POST	/mcp	JSON-RPC 2.0: initialize, tools/list, tools/call { name, arguments }	the result with structuredContent and _meta (widget, block, theme, jsonLd, payload, license); ETag the content hash, X-Qpu-Address the block address, X-Qpu-Version — errors: JSON-RPC -32601 (no such tool or method), -32602 (invalid params, with the bound the schema names), -32700 (parse error)	none for every pure tool; a tenant's tokens only for the docket
GET	/.well-known/qpu.json	nothing	the discovery document: mcp, docket, methods, tools, bounds, version, tenants, mcpHosts, roles, licence, the reverse (the unit)	none
GET	/	accept: application/json for the discovery document; otherwise the web OS	the discovery document or the site	none
GET	/<uuid> or /u/<uuid>	a content-addressed v8 UUID	the block's page (the widget, prev and next, the theme from the UUID); immutable, ETag the address, 304 to If-None-Match	none
GET	/docket	?kind=&since=	the tenant's entries (one docket per tenant host)	none to read
GET	/docket/<id>	an entry id; ?cheap, ?heal	the entry, healed from a mirror by address when missing	none to read
POST	/docket	{ kind, from, body, links? } or a commitment { kind, from, address, sha256 }	201 with the entry id (content address); 400 on shape, 413 above the entry bound	Bearer: the tenant's writer token (QPU_WRITE_TOKEN_<TENANT>) or the RBAC MCP host's role
DELETE	/docket/&lt;id&gt;	an entry id	the entry gone	Bearer: the tenant's admin token
POST	/docket/stripe	a Stripe webhook, signed	the event as an entry, idempotent	STRIPE_WEBHOOK_SECRET_<TENANT>
GET	/health	nothing	status, tenant, licence and the metrics computed now	none

Headers

Request	Response
content-type: application/json	etag: the content hash of the result (the clock masked)
accept: application/json or text/event-stream	x-qpu-address: the block address (uuidOf(tool + arguments))
if-none-match: "<content hash>" — a 304 answers with no body when the block is the one held	x-qpu-version
authorization: Bearer <tenant token> (the docket's writes only)	cache-control: public, max-age=31536000, immutable on addressed replies
	link: <https://uuidna.com/license>; rel="license"

Authorization

• pure: every tool answers without a credential: the tools are pure functions of their arguments
• docket: roles reader, writer, admin per tenant: the RBAC MCP host first (QPU_RBAC_MCP, QPU_RBAC_TOOL), else the tenant's tokens by name; a token at another tenant's host holds no role there
• never: no key, token or secret travels through a tool; the client sends them, the tools name them

Content addressing and the involution

• address: uuidOf(tool + JSON(arguments)): the same arguments at any host give the same address
• hash: the content hash of the result with the clock masked: the same code gives the same hash at any host
• involution: a request naming the hash with If-None-Match is answered 304: the analog is verified digitally at the destination, nothing computed or sent
• versions: versions coexist: an earlier version's addresses answer beside the new one's

Tools

42 tools in 12 toolboxes; every tool's schema is in the MCP reference and every example in the textbook.

Tool	Toolbox	What it answers
processor	google	A Google Quantum AI processor as its spec sheet states it: qubits, the grid, the two chips, and the magic-state figures.
circuit	google	Compile a circuit from its operations, placed by an insert strategy, and simulate it. Without noise or observables: the
echo	google	Quantum Echoes: run the operations forward, perturb once, run them back, and return the probability that every qubit ret
echo_benchmark	google	The Quantum Echoes result as Google states it: the processor, its qubits, the speedup, and the molecules.
roadmap	google	The Google Quantum AI roadmap: its six milestones, their physical-qubit scale, and which are achieved or in progress. Wi
algorithm	google	The textbook algorithms of the Cirq page: qft and inverse_qft (on 1 to 6 qubits, from input x), phase_estimation (of θ w
software	google	The open-source tools of the Google Quantum AI Software page, as the page describes them. Only Cirq is implemented in th
statements	google	The statements quantumai.google, its PDFs and the quantumlib repositories make, each as the page states it: Cirq, the de
repositories	google	The repositories of the quantumlib GitHub organization, as its list states them: name, description and primary language.
quantumlib	google	The fifteen repositories of the quantumlib GitHub organization, each with what this repository implements of it: the exp
quantum-error-correction	google	The three-qubit repetition code, simulated on the density matrix: a logical qubit encoded, a channel (bit_flip, phase_fl
chemistry-simulation	google	Molecular hydrogen in STO-3G as a variational energy evaluation on the simulator: the integrals are computed here from t
fault-tolerant-design	google	Resource counts read from the circuits this repository builds: the QFT on n qubits, Grover, teleportation, Shor for N up
leads	tree	Every lead on quantumai.google (every page of its sitemap, read whole), its PDFs and the quantumlib repositories, with i
audit	tree	The surface audits itself through tools/call: every tool has a schema and an example, every documented example replays a
match	tree	Any statement, matched against everything the surface can do. served: a call answers it and is returned. impossible: the
clay	tree	The Clay register recomputed in exact integer arithmetic: the Lean definitions of Qpu/Clay.lean and its imports ported o
verify	tree	Cheap verification of one UUID: its seal (the version nibble the other 31 nibbles decide, one modular power, no content
metrics	tree	The computable metrics of this tree in real time: tools and toolboxes, examples and how many name the kernel-accepted th
textbook	tree	The QPU textbook as an adapter: every example categorised for reuse — by toolbox, by tool, by the kernel-accepted theore
css	tree	The quantum UI as CSS alone: the stylesheet derived from the key 432 (the harmonics, and the rules that draw every block
dashboard	tree	A bounded tool laid out whole, so the user's decision in the UI is final: every value each property admits (an enum, a b
clone	tree	A toolbox cloned whole: its toolset (every tool's name, description and schema), its skillset (idea, instructions, direc
discover	flow	Discovery before use. Without answers: every request the client must make for the contracts of the hosts this tree talks
wave	flow	The verification wave. Without results: every request the surface's leads and tree facts need, once per URL with the lea
readiness	flow	The unit judges the tree. Phase one (verification, discovery, present, ledger): every lead judged by measurement into se
imagine	flow	Imagination leads all leads: every lead (or the subset named) matched with the reflection on — hidden factors, angles, m
e2e	flow	The end-to-end gate as a repetition code. Without answers: every combination the dashboards lay out and every example of
shard	flow	A long single task split into short multitasks: the share of a list among n shards (index, count) is every item whose po
translate	language	Translation by vocabulary, offline, both ways: text, from, to. A word no table knows stays as it is and is reported, nev
prose	language	Programmable prose: call a tool with its arguments and render its result as sentences in a locale — the toolbox's idea,
mongo	raid	The ported MongoDB over the docket, pure. find: {collection, docs, filter, sort, skip, limit} → the matching documents (
stripe	billing	Stripe per tenant, pure, the QPU as a product with its variants. catalogue: every product and variant (domain, tenant, s
legal	legal	The full legal and security audit with forensic analysis, through MCP. Phase one (texts, discovery, agents?, theoremKeys
repository	repository	Workspaces, branches, tags and releases watched and verified online, pure. Phase one (local): the requests to GitHub (br
jsonld	standards	schema.org JSON-LD, pure: for a block (tool, id, description), a page (url, title, description, uuid?) or an offer of th
codes	standards	The tree's ISO codes validated against the CLDR lists a client fetched (languages ISO 639, currencies ISO 4217, territor
payload	payload	Any tool's result as the document Payload's default plugins hold, no custom collection: a lexical document whose one blo
configure	payload	MCP configures Payload and the rest: Payload's default plugins (lexical with the one qpu block, nested-docs, seo, search
extend	extension	QPU as the natural extension of every MCP and every MCP of QPU. Inward (host, tools): the host's tools/list read into do
fold	crypto	The split folds: a payload larger than a place can hold is folded into pieces under the bound (bytes), each addressed by
seal	crypto	SHA-256 of a text, and HMAC-SHA256 under a key the caller gives (a test key; a tenant's secret never travels here), pure

The MCP connector

A Claude request mounts this catalogue through the Messages API's MCP connector (both halves, the server and its toolset):

{
  "endpoint": "https://api.anthropic.com/v1/messages",
  "betas": [
    "mcp-client-2025-11-20"
  ],
  "mcp_servers": [
    {
      "type": "url",
      "url": "https://qpu.uuidna.com/mcp",
      "name": "qpu"
    }
  ],
  "tools": [
    {
      "type": "mcp_toolset",
      "mcp_server_name": "qpu"
    }
  ]
}

Any other MCP client mounts it as:

{
  "mcpServers": {
    "qpu": {
      "url": "https://qpu.uuidna.com/mcp"
    }
  }
}

Quick tests

list the tools:

curl -s https://qpu.uuidna.com/mcp -X POST -H 'content-type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

the Clay register read by reflection:

curl -s https://qpu.uuidna.com/mcp -X POST -H 'content-type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"clay","arguments":{"technique":"reflection"}}}'

the involution: ask with the hash and receive 304:

curl -si https://qpu.uuidna.com/mcp -X POST -H 'content-type: application/json' -H 'if-none-match: "<etag of the reply above>"' -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"clay","arguments":{"technique":"reflection"}}}'

the discovery document:

curl -s https://qpu.uuidna.com/.well-known/qpu.json

Limits

• shorN: 21
• qubits: 6
• entry: the docket's entry bound (413 above it; fold splits what a place cannot hold)
• quantum: a client's run stops at QPU_QUANTUM_MS and keeps what it settled

Errors

Code	Means
-32601	no such tool or method; the answer names the tools
-32602	invalid params; the answer names the bound the schema sets
-32700	parse error
HTTP 304	the block held is the block asked: nothing sent
HTTP 400	an entry's shape refused, named
HTTP 401	a token with no role at this tenant
HTTP 413	an entry above the bound: fold it