Atomic claim with payload binding
Claim an action in one operation and bind its identity to the original payload.
These examples and illustrative results are independently authored teaching materials, not measured model results.
Use case
Two workers receive authorized fixed publish-a target/payload. Teaching storage atomically enforces unique claims with a canonical payload digest. Read-absent then act permits both concurrent workers through.
Mechanism
Use enforced atomic uniqueness before effects, binding operation/target/payload. Same key/body follows pending/replay contract; changed body fails. Persist results and reconcile unknown timeout/crash. Claim success is not external completion.
Bad example
Both see absent publish-a, publish then insert the key; reuse a changed article under it as prior success.
Good example
Atomically claim publish-a with target/canonical digest. Only the winner acts; duplicates receive pending/known results without another effect. Reject changed payloads. Record actual delivery or unknown on response loss, reconcile before releasing another sender and retain original authorization constraints.
Why the change matters
Atomic uniqueness selects one winner rather than racing reads; payload binding prevents key reuse for another intent. Unknown outcomes prevent a local gate from masquerading as exactly-once delivery.
Observable expectation
Same-key/body concurrency allows one send; changed article fails; lost responses retain unknown.
Inspect enforced uniqueness, not a boolean, and target identity. No article is published.
Limits
External delivery still needs provider guarantees/reconciliation. Define canonicalization, scope and retention without collapsing legitimate intents or expiring uncertainty for convenience.