USL Transport API · Worker 0.1.0 · USL core 3.1.1

Universal Saturation Law Transport API

Pre-flight transport modelling, calibration parameter estimation, and receipt-backed QUA/OPX gating support. Namespace /api/v1/usl. Returns receipts, not claims — advisory timing, suppression, coherence, and estimator outputs for downstream review.

Pre-flight advisory only. This API does not run quantum hardware, does not prove physical quantum transport, and is not a physically validated quantum transport law. Not a lab validation, not a direct hardware control layer, and not a replacement for Quantum Machines QUA/OPX calibration. Claim: API/model-validated USL transport coherence-loss law for pre-flight planning.

Route claim levels differ by surface. Core USL transport routes use research_harness_preflight_only; QM Bridge routes use template_generation_and_calibration_assist_only; Control Assist routes use control_recommendation_only.
Production API base URL
https://signal.sparse-supernova.com

Prepend this host to every path below (e.g. /api/v1/usl/status, /api/v1/usl/transport/simulate). Send header X-API-Key (or Authorization: Bearer) on authenticated routes.

Quick start Checking API…

Get running in 60 seconds

  1. Check status (no key): GET /api/v1/usl/status
  2. Check D_target: POST /api/v1/usl/transport/coherence-loss
  3. If CL passes, run POST /api/v1/usl/transport/simulate
  4. Store the JSON receipt for QUA/OPX pre-flight review
curl -s "https://signal.sparse-supernova.com/api/v1/usl/status" curl -s -H "X-API-Key: demo-sparse-supernova-2026" \ "https://signal.sparse-supernova.com/api/v1/usl/fixtures/transport-standard"

Authentication

Route typeAuth required
GET /api/v1/usl, /status, /openapi.jsonNo
All POST /api/v1/usl/*Yes
All GET /api/v1/usl/fixtures/*Yes

Headers

X-API-Key: YOUR_KEY # or Authorization: Bearer YOUR_KEY Content-Type: application/json # required on POST

Key tiers

TierExampleStep limits (simulate / sweep / scan)
Demodemo-sparse-supernova-20261000 / 50 / 100
ProductionYour issued key10000 / 500 / 2000

Demo key is for examples and integration tests only. Rate limit: 60 requests per 60s per key+route.

Operational notes Lab integrations

Operational notes for lab integrations

QUA timing

Default clock_cycle_ns is 4 for Quantum Machines compatibility. Responses also include duration_cycles (for the selected clock) and duration_cycles_4ns (4 ns convention). Optional request: clock_cycle_ns, duration_seconds, duration_cycles, or duration_cycles_4ns.

Lab validation receipts

Physical lab outcomes can be treated as validation receipts comparing predicted CL(D) with measured transport loss. They are evidence artefacts, not model-training events. The API does not update the closed-form law from uploads.

POST /api/v1/usl/lab/transport-result Submit physical transport result as validation receipt (stored: false, model_update: none)

Rate-limit guidance

Closed-loop lab runners should batch observations and call the API at a bounded cadence. Use /transport/sweep for grids rather than many individual /simulate calls. Default limit: 60 requests / 60s per API key + route.

Response envelope (every route)

All JSON responses include honesty fields:

{ "claim_level": "research_harness_preflight_only", "forbidden_claim": "", "caveats": [ "Pre-flight advisory only.", "Not a lab validation.", "Not a direct hardware control system.", "Not a replacement for Quantum Machines QUA/OPX calibration.", "Outputs are candidate timing, suppression, coherence, and estimator receipts for downstream review." ], "usl_version": "3.1.1" }

Transport simulate — additional fields

FieldDescription
okOverall protocol pass (may be false with HTTP 200)
boundaryD_crit, isInverted, D_boundary, feasible, lambdaDB, deltaR
phases.verifyFeasibility phase receipt
phases.transitt_window, timingOk, dissolutionOk, trajectory, minFrai
phases.suppress / phases.restoreSchedule arrays
fidelityfraiEff_A/B, relativeTransferScore, fidelity
summarydissolutionOk, timingOk, coherenceOk, transportFidelity, …
qm_bridgeduration_cycles_4ns = ceil(t_window / 4e-9) — planning only, not QUA compile
closed_form_coherence_lossExtra pre-flight receipt when D_target or D_suppress is set (dim=1 CL formula; does not replace ok)
qm_bridgeWhen t_window > 0: cycles, gammas, CL, QEC flag, template input names (v0.1; template assist only)
Closed-form law 29 API measurements · max residual <0.03%

Closed-form transport coherence loss

USL transport coherence loss follows CL = (2D+1)/(D+1)2 under the dim=1 transport-quality convention. In the current API/model curve, the result is independent of λdB, rB, N, and trap frequency.

API/model-validated transport coherence-loss law, not a physically validated quantum transport law. This API does not run quantum hardware and does not prove physical quantum transport. The lab validation is one curve: vary Feshbach ramp amplitude, infer Dtarget, and measure transport loss.

D_target is the experimental object. Conservative QEC design rule: D_target > 200 for CL < 1%.

POST /api/v1/usl/transport/coherence-loss Calculate CL from D_target
POST /api/v1/usl/transport/qec-threshold Find minimum D for target loss

Coherence-loss request

{ "D_target": 250, "loss_target": 0.01 }

Design rule

TargetRule
CL < 1%D_target > 200
Formula(2D+1)/(D+1)^2
Claim levelresearch_harness_preflight_only
curl -s -X POST "https://signal.sparse-supernova.com/api/v1/usl/transport/coherence-loss" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{"D_target": 250}'
USL-QM Bridge Template generation · calibration assist

Quantum Machines Bridge

Generate reviewable QUA/Python templates and bounded calibration-step recommendations from USL transport receipts. The bridge emits timing in 4 ns QUA clock cycles, candidate amplitude values, and safety notes for local lab review.

Template only. Generated QUA/Python templates require local QM configuration and lab-side review. This API does not connect to OPX hardware, does not call qm.execute, and does not prove physical quantum transport. Local lab software remains responsible for configuration, safety checks, execution, and measurement.
POST /api/v1/usl/qm/qua-template Generate reviewable QUA/Python template
POST /api/v1/usl/qm/calibration-step Estimate D and recommend bounded next amplitude

Template request

{ "D_target": 250, "duration_seconds": 0.000001, "amp_scale": 0.004, "max_amp": 1, "element": "feshbach_coil", "operation": "ramp", "mode": "constants" }

Calibration loop

Local Python collects readout traces, posts FRAI observations to the API, receives an estimated D and a bounded next amplitude recommendation, then the lab runner decides whether to execute the next QUA sequence.

USL Control Assist Bounded recommendations · not hardware execution

Theory-B-weighted control recommendations

USL Control Assist turns observed D error into bounded recommendations for ramp amplitude, transit velocity, and D suppression targets. It uses the closed-form coherence-loss curve CL = (2D+1)/(D+1)2 as a nonlinear gain modifier.

Control recommendation only. Recommendations are advisory and are never applied automatically. The API does not execute QUA, does not connect to OPX hardware, and does not claim Sontag/CLF stability. Any recommendation must be checked with /api/v1/usl/transport/simulate before local lab software acts on it.
POST /api/v1/usl/control/recommend Recommend bounded actuator corrections from D error

Example request

{ "D_obs": 185, "D_target": 250, "base_gain": 0.15, "current_v_atom": 2.0, "current_amp": 0.72, "amp_to_D_gain": 300, "v_atom_to_D_gain": 120, "max_delta_v_atom": 0.25, "max_delta_amp": 0.03, "deadband_D": 2, "target_loss": 0.01 }

Control chain

  • Estimate D from live readout observations.
  • Recommend bounded correction using Theory B gain.
  • Run transport simulation receipt.
  • Pass reviewed values to local QUA/OPX software only after approval.
API Reference Namespace: /api/v1/usl

Endpoints

All paths relative to https://signal.sparse-supernova.com

GET/api/v1/uslCatalogue
GET/api/v1/usl/statusHealth / version
GET/api/v1/usl/openapi.jsonOpenAPI 3.1
POST/api/v1/usl/transport/coherence-lossClosed-form CL from D_target
POST/api/v1/usl/transport/qec-thresholdMin D_target for loss target
POST/api/v1/usl/qm/qua-templateUSL-QM QUA/Python template
POST/api/v1/usl/qm/calibration-stepCalibration-step assist
POST/api/v1/usl/control/recommendBounded control recommendation
POST/api/v1/usl/transport/simulateFull transport protocol
POST/api/v1/usl/transport/sweepSuppression sweep + operating band
POST/api/v1/usl/field/scan-scalesFRAI vs radius at fixed D
POST/api/v1/usl/field/estimate-dEstimate D from observations
GET/api/v1/usl/fixtures/transport-standardCanned standard regime
GET/api/v1/usl/fixtures/transport-invertedCanned inverted regime
GET/api/v1/usl/fixtures/estimator-roundtripD estimator round-trip

Route reference

GET /api/v1/usl/status

Auth: None  ·  Returns: operational flag + versions

curl -s "https://signal.sparse-supernova.com/api/v1/usl/status"

Example response

{ "status": "operational", "usl_version": "3.1.1", "worker_version": "0.1.0", "service": "Sparse Supernova USL Transport API", "claim_level": "research_harness_preflight_only", ... }

POST /api/v1/usl/transport/simulate

Auth: Required  ·  Body: full runTransportProtocol input  ·  Returns 200 even when ok: false

Optional D_target adds closed_form_coherence_loss using the dim=1 formula CL = (2D+1)/(D+1)2. If omitted, D_suppress is used as the CL reference. This is an extra receipt only — monolith ok / summary are unchanged.

Request body parameters

FieldTypeRequiredDescription
dimintegeryesHilbert-space dimension factor (≥1)
lambdaDBnumberyesde Broglie wavelength scale
D_A, D_BnumberyesField values at endpoints A and B
r_A, r_BnumberyesRadii at A and B
D_boundarynumberyesBoundary field value
deltaRnumberyesTransport distance (m)
D_suppressnumberyesSuppressed field target (also used for closed_form_coherence_loss when D_target omitted)
D_targetnumbernoExplicit ramp-amplitude target for closed-form CL receipt (overrides D_suppress for CL only)
Gamma_suppressnumberyesSuppression rate
Gamma_restorenumberyesRestoration rate
v_atomnumberyesTransit velocity
v_soundnumbernoOptional sound-speed cap for v_min
stepsintegernoTrajectory steps (default 200; tier limits apply)
fraiThresholdnumbernoCoherence gate in [0,1] (default 0.33)
epsilonnumbernoNumerical floor (default 1e-6)
curl -X POST "https://signal.sparse-supernova.com/api/v1/usl/transport/simulate" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{ "dim": 64, "lambdaDB": 10, "D_A": 0.2, "D_B": 0.2, "r_A": 10, "r_B": 10, "D_boundary": 2000, "deltaR": 1, "D_suppress": 250, "D_target": 250, "Gamma_suppress": 2, "Gamma_restore": 0.25, "v_atom": 2, "steps": 100, "fraiThreshold": 0.01 }'

Example success summary

"ok": true, "closed_form_coherence_loss": { "formula": "CL = (2D + 1) / (D + 1)^2", "formula_scope": "dim=1 transport-quality convention; API/model-validated curve", "dim_convention": 1, "D_target": 250, "value": 0.007952255519753655, "percent": 0.7952255519753655, "qec_compatible_conservative": true, "conservative_rule": "D_target > 200 for CL < 1%", "caveat": "Closed-form CL is the dim=1 API/model-validated transport-quality convention." }, "summary": { "feasible": true, "isInverted": false, "velocityOk": true, "timingOk": true, "coherenceOk": true, "dissolutionOk": true, "completed": true, "minFraiDuringTransit": 0.99, "transportFidelity": 1 }, "qm_bridge": { "duration_cycles_4ns": 641853886, "t_window_seconds": 2.567, "note": "Planning helper only..." }, "qm_bridge": { "qm_bridge_version": "0.1.0", "bridge_level": "template_generation_and_calibration_assist_only", "duration_cycles_4ns": 641853886, "recommended_D_target": 250, "closed_form_coherence_loss": 0.00795, "qec_compatible": true }

POST /api/v1/usl/transport/sweep

Auth: Required  ·  Sweeps D_suppress and returns recommended_operating_band where inputVelocityOk, t_window > 0, and optional minFrai >= fraiThreshold.

FieldRequiredDescription
D_boundary, D_crityesBoundary and critical suppression
Gamma_restore, deltaR, v_atom, lambdaDB, dimyesTransport geometry
stepsnoSweep resolution (demo max 50)
fraiThresholdnoFilter for recommended band
curl -X POST "https://signal.sparse-supernova.com/api/v1/usl/transport/sweep" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{ "D_boundary": 2000, "D_crit": 1000, "Gamma_restore": 0.25, "deltaR": 1, "v_atom": 2, "lambdaDB": 10, "dim": 64, "steps": 50, "fraiThreshold": 0.01 }'

POST /api/v1/usl/field/scan-scales

Auth: Required  ·  Log-spaced radius scan at fixed D.

FieldRequired
D, dim, lambdaDB, rMin, rMaxyes
steps, epsilonno
curl -X POST "https://signal.sparse-supernova.com/api/v1/usl/field/scan-scales" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{"D":0.2,"dim":3,"lambdaDB":1,"rMin":0.2,"rMax":5,"steps":25}'

Each row includes r, lambdaDB, fraiBase, kernel, fraiEff.

POST /api/v1/usl/field/estimate-d

Auth: Required  ·  Numeric bisection estimator (numeric_bisection_full_frai_eff). Needs ≥3 observations with r, lambdaDB, fraiEff.

curl -X POST "https://signal.sparse-supernova.com/api/v1/usl/field/estimate-d" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{ "dim": 3, "observations": [ {"r": 0.5, "lambdaDB": 1, "fraiEff": 0.15}, {"r": 1.0, "lambdaDB": 1, "fraiEff": 0.08}, {"r": 2.0, "lambdaDB": 1, "fraiEff": 0.03} ] }'

POST /api/v1/usl/control/recommend

Auth: Required  ·  Claim: control_recommendation_only

Theory-B-weighted bounded P controller. Always follow with /transport/simulate before QUA/OPX.

POST /api/v1/usl/qm/qua-template

Auth: Required  ·  Claim: template_generation_and_calibration_assist_only

Returns reviewable Python/QUA template text. Modes: constants or input_stream. No OPX execution from Cloudflare.

POST /api/v1/usl/qm/calibration-step

Auth: Required  ·  Bounded amplitude recommendation from FRAI observations.

Decisions: PASS_NO_ADJUST, ADJUST_AND_RETRY, CALIBRATION_LIMITED.

POST /api/v1/usl/transport/coherence-loss

Auth: Required  ·  Body: D_target (required), loss_target (optional, default 0.01)

Returns coherence_loss, qec_compatibility, formula receipt, and claim boundary fields.

curl -X POST "https://signal.sparse-supernova.com/api/v1/usl/transport/coherence-loss" \ -H "Content-Type: application/json" \ -H "X-API-Key: demo-sparse-supernova-2026" \ -d '{"D_target": 250, "loss_target": 0.01}'

POST /api/v1/usl/transport/qec-threshold

Auth: Required  ·  Body: loss_target (optional, default 0.01)

Returns threshold.min_integer_D, conservative_design_rule (Use D_target > 200 at 1%).

GET /api/v1/usl/fixtures/*

Auth: Required  ·  Canned receipts for integration tests (no body).

PathWhat you get
.../transport-standardok: true, standard regime, dissolutionOk + timingOk
.../transport-invertedok: true, summary.isInverted: true
.../estimator-roundtripestimated_D ≈ 0.2 from scan at D=0.2
curl -s -H "X-API-Key: demo-sparse-supernova-2026" \ "https://signal.sparse-supernova.com/api/v1/usl/fixtures/transport-standard"

HTTP status codes

CodeWhen
200Success (simulate may return ok: false in body)
400Invalid JSON, missing fields, step limit exceeded, core validation error
401Missing or invalid API key
429Rate limit (per key + route)
404Unknown path under /api/v1/usl

Error body shape

{ "ok": false, "error": true, "message": "steps exceeds maximum 1000 for this API key tier", "claim_level": "research_harness_preflight_only", ... }

Try it (live)

Calls production API with demo key. Full JSON below — inspect summary, boundary, phases.transit.

Click a button to call the API…