Hearth & Code ยท Fieldcrafthttps://hearthandcode.github.io/Practical techniques with working examples.Separate pure plans from released effectshttps://hearthandcode.github.io/separate-pure-plans-from-released-effects.htmlhttps://hearthandcode.github.io/separate-pure-plans-from-released-effects.htmlA two-mode checker that keeps pure planning distinct from authorized execution.Wed, 09 Sep 2026 00:00:00 GMTTransfer Rust ownership at a task boundaryhttps://hearthandcode.github.io/transfer-rust-ownership-at-task-boundaries.htmlhttps://hearthandcode.github.io/transfer-rust-ownership-at-task-boundaries.htmlA browser transfer model and compile-fail Rust ownership example for a single task packet.Wed, 09 Sep 2026 00:00:00 GMTMake parse failure explicit with Rust Resulthttps://hearthandcode.github.io/make-parse-failure-explicit-with-rust-result.htmlhttps://hearthandcode.github.io/make-parse-failure-explicit-with-rust-result.htmlA browser-aligned parser and compile-tested Rust Result example with explicit failure variants.Wed, 09 Sep 2026 00:00:00 GMTEncode review state with Rust typestatehttps://hearthandcode.github.io/encode-review-state-with-rust-typestate.htmlhttps://hearthandcode.github.io/encode-review-state-with-rust-typestate.htmlA browser model and compile-tested Rust typestate example for draft and reviewed articles.Wed, 09 Sep 2026 00:00:00 GMTCap deterministic retry backoffhttps://hearthandcode.github.io/cap-deterministic-retry-backoff.htmlhttps://hearthandcode.github.io/cap-deterministic-retry-backoff.htmlA deterministic retry calculator with an explicit attempt budget and delay cap.Wed, 09 Sep 2026 00:00:00 GMTDo not redispatch an indeterminate model stephttps://hearthandcode.github.io/hold-indeterminate-model-steps.htmlhttps://hearthandcode.github.io/hold-indeterminate-model-steps.htmlA pedagogical lifecycle checker that holds redispatch after a model step becomes indeterminate.Wed, 09 Sep 2026 00:00:00 GMTDetect idempotency-key conflictshttps://hearthandcode.github.io/detect-idempotency-key-conflicts.htmlhttps://hearthandcode.github.io/detect-idempotency-key-conflicts.htmlA deterministic idempotency check that distinguishes new requests, replay, conflict and duplicate history.Wed, 09 Sep 2026 00:00:00 GMTCheck producer and consumer compatibilityhttps://hearthandcode.github.io/check-producer-consumer-compatibility.htmlhttps://hearthandcode.github.io/check-producer-consumer-compatibility.htmlA bounded required-field compatibility check for a typed producer-consumer seam.Wed, 09 Sep 2026 00:00:00 GMTReturn a loss report with every projectionhttps://hearthandcode.github.io/return-a-projection-loss-report.htmlhttps://hearthandcode.github.io/return-a-projection-loss-report.htmlA shallow scalar projection checker that compares actual and declared loss.Wed, 09 Sep 2026 00:00:00 GMTKeep capability separate from permissionhttps://hearthandcode.github.io/capability-permission-exact-scope.htmlhttps://hearthandcode.github.io/capability-permission-exact-scope.htmlA checker that prevents technical capability or adjacent scope from becoming authority.Wed, 09 Sep 2026 00:00:00 GMTFail closed when a guard state is unknownhttps://hearthandcode.github.io/fail-closed-unknown-guard.htmlhttps://hearthandcode.github.io/fail-closed-unknown-guard.htmlA tri-state guard checker that treats unknown as a hold with visible evidence.Wed, 09 Sep 2026 00:00:00 GMTReject stale retrieval evidence at an explicit boundaryhttps://hearthandcode.github.io/reject-stale-retrieval-evidence.htmlhttps://hearthandcode.github.io/reject-stale-retrieval-evidence.htmlReject evidence that exceeds a stated maximum age while accepting the exact boundary.Wed, 09 Sep 2026 00:00:00 GMTSeparate evidence confidence from release statushttps://hearthandcode.github.io/separate-evidence-confidence-from-release-status.htmlhttps://hearthandcode.github.io/separate-evidence-confidence-from-release-status.htmlKeep evidence confidence and release lifecycle in independent fields rather than deriving one from the other.Wed, 09 Sep 2026 00:00:00 GMTExplain a revision with set differenceshttps://hearthandcode.github.io/explain-a-revision-with-set-differences.htmlhttps://hearthandcode.github.io/explain-a-revision-with-set-differences.htmlUse added and removed set members to give a compact, reproducible revision explanation.Wed, 09 Sep 2026 00:00:00 GMTPreserve source offsets when extracting spanshttps://hearthandcode.github.io/preserve-utf-16-source-offsets.htmlhttps://hearthandcode.github.io/preserve-utf-16-source-offsets.htmlCheck extracted spans against JavaScript UTF-16 code-unit offsets, including surrogate-pair boundaries.Wed, 09 Sep 2026 00:00:00 GMTSelect context by relevance under a token budgethttps://hearthandcode.github.io/select-context-within-a-token-budget.htmlhttps://hearthandcode.github.io/select-context-within-a-token-budget.htmlA deterministic greedy selector that prioritizes relevance while keeping within a declared token budget.Wed, 09 Sep 2026 00:00:00 GMTDetect cycles in a dependency graphhttps://hearthandcode.github.io/detect-dependency-cycles.htmlhttps://hearthandcode.github.io/detect-dependency-cycles.htmlUse depth-first traversal to identify a directed dependency cycle before scheduling work.Wed, 09 Sep 2026 00:00:00 GMTPreserve minority conclusions during synthesishttps://hearthandcode.github.io/preserve-minority-conclusions.htmlhttps://hearthandcode.github.io/preserve-minority-conclusions.htmlA retention check that keeps every supplied conclusion, including minority positions, in a synthesis record.Wed, 09 Sep 2026 00:00:00 GMTSeparate contradiction from missing evidencehttps://hearthandcode.github.io/separate-contradiction-from-absence.htmlhttps://hearthandcode.github.io/separate-contradiction-from-absence.htmlClassify unsupported records separately from records that assert incompatible values for the same claim.Wed, 09 Sep 2026 00:00:00 GMTRequire every claim to name its evidencehttps://hearthandcode.github.io/bind-every-claim-to-evidence.htmlhttps://hearthandcode.github.io/bind-every-claim-to-evidence.htmlA claim-to-evidence checker that rejects claims with no named supporting record.Wed, 09 Sep 2026 00:00:00 GMTDetect source revision drift with explicit identityhttps://hearthandcode.github.io/detect-source-revision-drift.htmlhttps://hearthandcode.github.io/detect-source-revision-drift.htmlA small explicit check for source revision drift without treating a version label as cryptographic proof.Wed, 09 Sep 2026 00:00:00 GMTCheck design contrast with the WCAG formulahttps://hearthandcode.github.io/check-design-contrast-with-wcag-formula.htmlhttps://hearthandcode.github.io/check-design-contrast-with-wcag-formula.htmlCalculate relative luminance and compare a synthetic color pair with a declared contrast threshold.Wed, 09 Sep 2026 00:00:00 GMTChoose a diverse concept set with declared tagshttps://hearthandcode.github.io/choose-a-diverse-concept-set-by-declared-tags.htmlhttps://hearthandcode.github.io/choose-a-diverse-concept-set-by-declared-tags.htmlCheck a synthetic concept set for unique identities, required tags and a declared diversity floor.Wed, 09 Sep 2026 00:00:00 GMTSeparate the fixed brief from optional variationhttps://hearthandcode.github.io/separate-fixed-brief-from-optional-variations.htmlhttps://hearthandcode.github.io/separate-fixed-brief-from-optional-variations.htmlCheck that a synthetic creative candidate keeps fixed brief fields and uses only declared optional fields and values.Wed, 09 Sep 2026 00:00:00 GMTVary one creative parameter at a timehttps://hearthandcode.github.io/vary-one-creative-parameter-at-a-time.htmlhttps://hearthandcode.github.io/vary-one-creative-parameter-at-a-time.htmlCompare two synthetic creative candidates and require exactly one declared parameter to differ.Wed, 09 Sep 2026 00:00:00 GMTScore a creative candidate with declared criteriahttps://hearthandcode.github.io/score-a-creative-candidate-with-explicit-criteria.htmlhttps://hearthandcode.github.io/score-a-creative-candidate-with-explicit-criteria.htmlApply explicit weighted criteria to a synthetic creative candidate without calling the score a quality verdict.Wed, 09 Sep 2026 00:00:00 GMTCarry the constraints across a handoffhttps://hearthandcode.github.io/preserve-task-constraints-during-handoff.htmlhttps://hearthandcode.github.io/preserve-task-constraints-during-handoff.htmlCheck that required and optional task constraints survive a synthetic handoff.Wed, 09 Sep 2026 00:00:00 GMTStop refinement at a declared budgethttps://hearthandcode.github.io/stop-at-a-bounded-iteration-budget.htmlhttps://hearthandcode.github.io/stop-at-a-bounded-iteration-budget.htmlVerify that a refinement trace stays within its iteration budget and records one entry per iteration.Wed, 09 Sep 2026 00:00:00 GMTKeep a simple baseline in the comparisonhttps://hearthandcode.github.io/compare-against-a-simple-baseline.htmlhttps://hearthandcode.github.io/compare-against-a-simple-baseline.htmlCompare declared numeric criteria with a baseline and an explicit margin.Wed, 09 Sep 2026 00:00:00 GMTCheck output shape before the next stephttps://hearthandcode.github.io/validate-output-shape-before-use.htmlhttps://hearthandcode.github.io/validate-output-shape-before-use.htmlReject missing fields and wrong item types before a downstream operation reads an output.Wed, 09 Sep 2026 00:00:00 GMTTreat prompt fields as data, not separatorshttps://hearthandcode.github.io/delimiter-collisions-in-prompt-input.htmlhttps://hearthandcode.github.io/delimiter-collisions-in-prompt-input.htmlTest whether a prompt transport preserves items that contain its separator.Wed, 09 Sep 2026 00:00:00 GMTMake the acceptance condition executablehttps://hearthandcode.github.io/acceptance-condition.htmlhttps://hearthandcode.github.io/acceptance-condition.htmlOne independent acceptance predicate, a runnable example, and a counterexample.Wed, 09 Sep 2026 00:00:00 GMT