Verified calculation capability

Guard Band Calculation Capability

Simple guard band GB=k·u with optional acceptance limits. Not ILAC G8 / JCGM 106 risk-based decision rules. · Engineering · Process

Capability ID engineering.process.guard_band · version 1.0.0

Open calculator REST API MCP Evidence Evidence JSON CVP Manifest Review policy

Model

Guard band

Guard band: GB = k · u
Accept USL: A_USL = USL − GB
Accept LSL: A_LSL = LSL + GB

Inputs / Outputs

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

Symbol	Quantity	Unit	Role
`u`	Standard uncertainty	—	input / output
`k`	Coverage factor (default 2)	—	input / output
`usl`	Upper specification limit (optional)	—	input / output
`lsl`	Lower specification limit (optional)	—	input / output
`GB`	—	—	output
`accept_usl`	—	—	output
`accept_lsl`	—	—	output

Assumptions / Validity

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

Assumptions

GB = k·u with k default 2
Not ILAC G8 / JCGM 106 risk-based decision rules
USL and LSL optional; omitted limits skip that acceptance output
Not Cp/Cpk and not Monte Carlo

Not supported

ILAC G8 / JCGM 106 risk tables
one-sided risk
Cp/Cpk
Monte Carlo

Example

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

u=0.5 k=2 usl=12 lsl=0 → GB=1 accept_usl=11 accept_lsl=1

Open this example in the calculator

Trust

CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · Simple guard band GB=k·u (k default 2) and optional A_USL/A_LSL + O3 mpmath tabulated GB.. 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 · Simple guard band GB=k·u (k default 2) and optional A_USL/A_LSL + O3 mpmath tabulated GB.· View Manifest · CVP overview · Specification
Verified scope: Simple guard band GB=k·u (k default 2) and optional A_USL/A_LSL + O3 mpmath tabulated GB.
Assurance: Engineering
Declared partition coverage: PASS · 6/6 declared partitions (default-k, explicit-k, two-sided, usl-only, lsl-only, invalid-domain)
Deferred: Not ILAC G8 / JCGM 106 consumer-producer risk tables, not Cp/Cpk, not Monte Carlo, and not a standalone Combined/Expanded page.
Calculation version: 1.0.0
Verification: 6/6 calculation tests · 1/1 legacy golden · 3/3 legacy boundary · 2/2 legacy property
Production surface contract: 4/4
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed · Evidence 2026-09-16.o2-o3
Verification revision: 2026-09-16.o2-o3 · 3/3 property · digest f0b6360d0f41
Reference: O1 model · O3 expected_values · O3 numerical_behavior · O2 expected_values · O2 numerical_behavior
Numerical scope: O2: GB=k·u and optional acceptance limits vs separate-module identities (≤2 ULP). Not ILAC G8 risk, not Cp/Cpk, not Monte Carlo. ≤2 ULP vs O3 applies only to the published tabulated GB vectors (default k, explicit k, two-sided, USL-only, LSL-only, u=0). It is not a whole-domain guarantee and does not cover ILAC G8 risk or Cp/Cpk.
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: 5/5 golden · 3/3 CVP boundary · 6/6 invalid · 3/3 property · 2/2 metamorphic · 8/8 O3 · 4/4 cross-interface · 4/4 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 4/4.

Tool id: guard-band
Engine: guard-band
REST: POST /api/v1/calc/guard-band
MCP: execute_calculation with capability_id: "engineering.process.guard_band"
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 this capability via same-origin MCP, then call execute_calculation.

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":"engineering.process.guard_band"}}}'

Inspect the trust tier and required assurance level before execution. Pin calculation_version (1.0.0) when reproducibility matters. Full protocol notes: MCP docs.