diff --git a/agentdescent/cli.py b/agentdescent/cli.py
index 2aa24f42..378cea62 100644
--- a/agentdescent/cli.py
+++ b/agentdescent/cli.py
@@ -309,10 +309,12 @@ def algorithm_override(name: Optional[str], params: Optional[Mapping[str, Any]],
     if params:
         params = algorithms._canonical_param_map(alg, params, where="algorithm.params")
     resolved = algorithms.resolve_params(alg, params)  # types/unknowns/choices
+    # Write the registered name, not the alias the user typed (`GEPA`,
+    # `archive-selection`), so the spec reads the same as `algorithms list`.
     if not params:
-        return name
+        return alg.name
     # Store user-supplied keys only, with coerced (folded) values (#888).
-    return {"name": name, "params": {k: resolved[k] for k in params}}
+    return {"name": alg.name, "params": {k: resolved[k] for k in params}}
 
 
 def missing_target_message(path: str) -> str:
diff --git a/changelog.d/894-init-algorithm-canonical-name.md b/changelog.d/894-init-algorithm-canonical-name.md
new file mode 100644
index 00000000..cda846cd
--- /dev/null
+++ b/changelog.d/894-init-algorithm-canonical-name.md
@@ -0,0 +1,5 @@
+Fixed
+`init --algorithm` writes the registered algorithm name into the spec, so
+`--algorithm GEPA` or `archive-selection` is saved as `gepa` /
+`archive_selection` (matching `algorithms list` and `algorithms run`) instead
+of the alias as typed (#894).
diff --git a/tests/test_algorithms.py b/tests/test_algorithms.py
index 542c2806..cc5e85e0 100644
--- a/tests/test_algorithms.py
+++ b/tests/test_algorithms.py
@@ -474,6 +474,27 @@ def test_init_writes_the_algorithm_and_only_the_params_given(tmp_path, capsys):
     assert "wrote" in capsys.readouterr().out
 
 
+def test_init_writes_the_registered_name_for_an_alias(tmp_path, capsys):
+    # #894: `init --algorithm GEPA` / `archive-selection` validated but wrote
+    # the alias verbatim into the spec.
+    prompt = tmp_path / "prompt.txt"
+    prompt.write_text("be terse\n")
+    assert cli.main(["init", str(prompt), "--out", str(tmp_path / "a.json"),
+                     "--algorithm", "GEPA", "--model", "m"]) == 0
+    assert json.loads((tmp_path / "a.json").read_text())["algorithm"] == "gepa"
+    assert cli.main(["init", str(prompt), "--out", str(tmp_path / "b.json"),
+                     "--algorithm", "RRSI", "--param", 'protected=["s"]',
+                     "--model", "m"]) == 0
+    assert json.loads((tmp_path / "b.json").read_text())["algorithm"] == {
+        "name": "rrsi", "params": {"protected": ["s"]}}
+    skill = tmp_path / "skill"
+    skill.mkdir()
+    (skill / "SKILL.md").write_text("---\nname: s\ndescription: d\n---\nbody\n")
+    assert cli.main(["init", str(skill), "--out", str(tmp_path / "c.json"),
+                     "--algorithm", "archive-selection", "--agent", "opencode"]) == 0
+    assert json.loads((tmp_path / "c.json").read_text())["algorithm"] == "archive_selection"
+
+
 def test_init_refuses_an_unknown_algorithm_or_wrong_kind(tmp_path, capsys):
     prompt = tmp_path / "prompt.txt"
     prompt.write_text("be terse\n")