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CVP verified calculation capability

Weir discharge Calculation Capability

Thin-plate weir discharge. Rectangular Q=(2/3) C_d L √(2g) H^{3/2}. Triangular Q=(8/15) C_d √(2g) tan(θ/2) H^{5/2}. Not Manning, not Q=Av, not Darcy, not an orifice, not Francis contractions.

Physics · Fluid Capability ID physics.fluid.weir version 1.0.0 CVP VERIFIED CURRENT Engineering

Model

Rectangular

Modes: rectangular · triangular

Inputs / Outputs

Canonical symbols for this capability. Agent schemas remain the contract.

SymbolQuantityUnitRole
HUpstream head above the crest in m—input / output
QDischarge in m³/s—input / output
LCrest length in m—input / output
theta_degV-notch angle in degrees—input / output
theta_radV-notch angle in radians—input
CdDischarge coefficient—input / output
gGravity in m/s²—input / output
model——output

Assumptions / Validity

Declared scope for this capability. Do not use it outside this domain.

Assumptions

Not supported

Example

One numerical check. The calculator page holds worked steps and FAQ.

L=1 H=0.2 → Q=(2/3)(0.62)(1)√(2g) H^{3/2}

Open this example in the calculator

Trust

CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · Thin-plate rectangular and triangular free-flow weir discharge, + O3 mpmath tabulated Q.. Computational verification is defined by CVP. Supplemental domain review (internal) and named expert review are defined by the Review policy and do not by themselves determine CVP conformance.

CVP
CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · Thin-plate rectangular and triangular free-flow weir discharge, + O3 mpmath tabulated Q.· View Manifest · CVP overview · Specification
Verified scope
Thin-plate rectangular and triangular free-flow weir discharge, + O3 mpmath tabulated Q.
Assurance
Engineering
Declared partition coverage
PASS · 5/5 declared partitions (rectangular, triangular, alias, awkward, invalid-domain)
Deferred
Not submerged H2, not orifice, not Manning, not Darcy, not Parshall/sluice/ogee/side.
Calculation version
1.0.0
Verification
15/15 calculation tests · 1/1 legacy golden · 9/9 legacy boundary · 5/5 legacy property
Production surface contract
5/5
Versions
Calculation 1.0.0 · CVP protocol 1.0.0-proposed · Evidence 2026-09-26.o2-o3
Verification revision
2026-09-26.o2-o3 · 1/1 property · digest cb016aee9f08
Reference
O1 model · O3 expected_values · O3 numerical_behavior · O2 expected_values · O2 numerical_behavior
Numerical scope
O2: thin-plate weir vs a separate-module identity (≤2 ULP). Not submerged H2, not orifice, not Manning, and not Darcy. ≤2 ULP vs O3 applies only to the published tabulated weir vectors. Not submerged H2, not orifice, not Manning, and not Darcy.
Interfaces
PASS · UI (SSR) / REST / MCP
ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only.
CVP suite
4/4 golden · 7/7 CVP boundary · 10/10 invalid · 1/1 property · 1/1 metamorphic · 8/8 O3 · 2/2 cross-interface · 5/5 CVP contract
Supplemental domain review
Not performed
Named expert review
Not performed
Version lock
Supported (409 VERSION_MISMATCH)
Artifact consistency
Build verified · 1.0.0 (workspace artifacts agree)
Review-policy tier
Engine tested — catalog token engine_tested; supplemental; not CVP status
This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

Call this capability

Human page, REST, and MCP share the same engine and calculation_version. Build verified hashes workspace artifacts only. After deploy, attest:production GETs canonical URLs twice — the public/cached view an Agent actually hits, and origin — including every /capabilities/{id} HTML page. Public Capability HTML version must match catalog before production attestation passes. Live Trust rows above fetch /.well-known/calculatorx-production-attestation.json and the output schema const. Build hashes: release integrity. That proves currently published page / engine / schema / evidence / MCP agree — not that a historical version is independently immutable. Reference Calculation Standard — Production surface contract 5/5.

curl -sS -X POST 'https://www.calculatorx.com/api/v1/calc/weir-discharge' \
  -H 'Content-Type: application/json' \
  -d '{"inputs":{"L":1,"H":0.2},"calculation_version":"1.0.0"}'

POST /api/v1/calc/weir-discharge. This is a POST calculate endpoint — do not GET it.

Full REST contract: REST API docs.

Tool id
weir-discharge
Engine
weir-discharge
REST
POST /api/v1/calc/weir-discharge
MCP
execute_calculation with capability_id: "physics.fluid.weir"
Agent input schema
Canonical (MCP / Agent)
Output schema
JSON Schema (latest)
Versioned input schema
Immutable pin (1.0.0)
Versioned output schema
Immutable pin (1.0.0)

References

Human-readable sources plus CVP reference evidence classes.

Sources

Reference evidence classes: O1 model · O3 expected_values · O3 numerical_behavior · O2 expected_values · O2 numerical_behavior

Try with an agent

Inspect, then execute. Same engine as REST and the human calculator.

curl -sS -X POST 'https://www.calculatorx.com/mcp' \
  -H 'Content-Type: application/json' \
  -H 'MCP-Protocol-Version: 2026-07-28' \
  -H 'Mcp-Method: tools/call' \
  -H 'Mcp-Name: inspect_capability' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"inspect_capability","arguments":{"capability_id":"physics.fluid.weir"},"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientInfo":{"name":"calculatorx-docs-example","version":"1.0.0"},"io.modelcontextprotocol/clientCapabilities":{}}}}'

Pin calculation_version (1.0.0) when the result must stay reproducible.

Inspect the trust tier and required assurance level before execution. Full protocol notes: MCP docs.