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AGENTS.md

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+# Repository Guidance
+
+This repository contains implementation-sensitive protocol text. Treat the current specification as already implemented by real applications.
+
+## Core Rule
+
+Do not change the meaning of current specification material during structural refactors.
+
+Preserve:
+
+- event kind numbers
+- tag names and tag ordering where shown in examples
+- tag array shapes
+- JSON payload shapes
+- field names
+- required/optional semantics
+- status and type values
+- examples
+- MUST, SHOULD, and MAY language
+- links to upstream specs and prior work
+
+## Current Compatibility Snapshot
+
+[SPEC.md](SPEC.md) is the contiguous current specification. It was copied from the pre-refactor root README and should remain available for implementers who need the old single-document shape.
+
+If split docs disagree with [SPEC.md](SPEC.md), treat [SPEC.md](SPEC.md) as the compatibility source for the current protocol.
+
+## Structural Refactors
+
+Structural PRs may:
+
+- move or copy text unchanged
+- add navigation
+- add compatibility notes
+- add history and acknowledgments
+- add clearly marked explanatory material
+- add clearly marked proposal workspaces
+
+Structural PRs must not:
+
+- invent new Nostr kinds
+- rename existing tags
+- rewrite examples
+- change payment, order, delivery, listing, review, or merchant-preference semantics
+- make escrow mandatory
+- make any marketplace a required custodian of funds
+- collapse external proposals into this spec as if they are already canonical
+
+## Normative Labels
+
+Use explicit labels:
+
+- Normative: current spec material or future accepted protocol requirements.
+- Explanatory: reader guidance that does not redefine protocol behavior.
+- Historical: prior work and acknowledgments.
+- Experimental: active proposals, design space, or integration notes.
+
+## Agent Notes
+
+Before editing, inventory kind numbers, tag names, examples, and normative keywords in affected sections. After editing, compare them again. Prefer exact copies over paraphrases when transposing current spec text.