# Read evidence, receipts and drift: synthetic exercise worksheet

Curriculum reviewed: 2026-10-25. Use public or synthetic data only.
Do not include client evidence, credentials, private identifiers or raw receipts.

## Goal
A synthetic drift investigation with a precise rerun recommendation and no silent refreeze.

## Outcomes
- Trace a producer step result into a ledger receipt
- Identify input, output and upstream evidence bindings
- Investigate supersession and observed dependency drift
- Separate private receipts, value-free attestations and Hosted signed acknowledgements

## Synthetic case
Describe a Sales report built from order headers and order lines. State which grain you intend and which independently established expectation you would compare.

## Review each lesson
### 1. Read a step result
Identify operation, status, check identity and actuals before recording.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 2. Follow a receipt graph
Trace retained hashes, declared dependencies and the limits of a signature.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 3. Understand frozen expectations
Read the catalogue, oracle definition and expected-value bindings without changing the lock.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 4. Investigate a stale result
Find the changed dependency and select the owning rerun rather than an older success.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 5. Use the atlas responsibly
Read lineage and boundary states while protecting value-bearing local evidence.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 6. Separate proof artifacts
Compare local receipts, signed value-free attestations and Hosted ACKs.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

## Failure case
Generated definitions exist but a required execution observation is missing. Explain why qualification cannot pass and name the next required observation. Do not fabricate a receipt or change a frozen expectation.

## Evidence table
| Claim | Expected observation | Available evidence | Missing/stale | Next owner/action |
| --- | --- | --- | --- | --- |
| | | | | |

## Limitations
This worksheet is a completion check, not live qualification, business acceptance or a professional award. Pro assessment and certification policy remain planned. Keep optional live results in customer-controlled custody.