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 # postgresql-tenant-operator - AI Agent Guide
 
+## Specification-Driven Development
+
+- Use specification-driven development for every new feature and externally observable
+  behavior change: decide and document the contract before writing implementation code.
+- Create or update the relevant specification first. It must define scope, non-goals,
+  observable behavior, validation, failure semantics, security boundaries, and acceptance
+  criteria at the level needed for a human to make the pending decisions.
+- Stop after the specification reaches a reviewable state and ask the user to approve it
+  before implementing the behavior. Approval of a plan, issue, or earlier specification
+  does not imply approval of materially new decisions.
+- Derive tests from the approved acceptance criteria, then implement the smallest vertical
+  slice that makes those tests pass. Keep specification, tests, and implementation
+  traceable to one another.
+- If implementation exposes an ambiguity or requires changing the approved behavior, stop,
+  update the specification, and request review again before continuing.
+- Keep specifications focused on contracts and decisions. Do not prematurely freeze internal
+  Go package structure, function names, or SQL details unless they are part of the contract.
+
 ## Human-Reviewable Changes
 
 - Break every feature into small, coherent changes that a human can review independently.