diff --git a/src/idea194_attractorforge_verified_attractor/compiler.py b/src/idea194_attractorforge_verified_attractor/compiler.py
index fd4e827..e301629 100644
--- a/src/idea194_attractorforge_verified_attractor/compiler.py
+++ b/src/idea194_attractorforge_verified_attractor/compiler.py
@@ -67,6 +67,16 @@ def _merkle_root(items: list[str]) -> str:
     return level[0]
 
 
+def _fingerprint(spec: AttractorSpec, gain: tuple[float, ...], controller_hash: str) -> str:
+    """Deterministic fingerprint for quick admission/indexing.
+
+    Combines a few stable, low-entropy fields and hashes them. This is
+    intentionally small and deterministic so it can be exchanged over DTN.
+    """
+    payload = _json({"spec_id": spec.spec_id, "kind": spec.kind, "gain_len": len(gain), "ctrl": controller_hash})
+    return _hash_text(payload)
+
+
 class AttractorCompiler:
     def compile(self, spec: AttractorSpec) -> CompilationResult:
         spec = spec.normalized()
@@ -80,6 +90,7 @@ class AttractorCompiler:
             estimated_basin_radius=spec.basin_radius,
             convergence_rate_bound=spec.convergence_rate,
             controller_hash=_hash_text(_json({"gain": gain, "target": spec.target_state, "kind": spec.kind})),
+            attractor_fingerprint=_fingerprint(spec, gain, _hash_text(_json({"gain": gain, "target": spec.target_state, "kind": spec.kind}))),
             dt=spec.dt,
         )
         return CompilationResult(controller=controller, plan_cert=plan_cert, plan_delta=plan_delta, basin_sketch=basin_sketch)
diff --git a/src/idea194_attractorforge_verified_attractor/models.py b/src/idea194_attractorforge_verified_attractor/models.py
index 909d7d4..f2ae756 100644
--- a/src/idea194_attractorforge_verified_attractor/models.py
+++ b/src/idea194_attractorforge_verified_attractor/models.py
@@ -65,6 +65,7 @@ class BasinSketch:
     estimated_basin_radius: float
     convergence_rate_bound: float
     controller_hash: str
+    attractor_fingerprint: str
     dt: float
 
 
diff --git a/tests/test_compiler.py b/tests/test_compiler.py
index 7b13a73..b5a2208 100644
--- a/tests/test_compiler.py
+++ b/tests/test_compiler.py
@@ -23,6 +23,9 @@ def test_motion_template_compiles_and_replays() -> None:
     assert replay.matched
     assert result.plan_cert.spec_id == spec.spec_id
     assert result.basin_sketch.controller_hash
+    # fingerprint should be a deterministic hex sha256 (64 chars)
+    assert isinstance(result.basin_sketch.attractor_fingerprint, str)
+    assert len(result.basin_sketch.attractor_fingerprint) == 64
     assert abs(replay.final_state[0]) < 0.8
     assert abs(replay.final_state[1]) < 0.8