diff --git a/internals/checks/testing-conventions.toml b/internals/checks/testing-conventions.toml
index ad1536649..4375f031c 100644
--- a/internals/checks/testing-conventions.toml
+++ b/internals/checks/testing-conventions.toml
@@ -15,7 +15,7 @@
 # its own config drops that phantom root; a change to decide.py's path list still
 # demands a receipt through the normal --scope internals/checks/src walk.
 [python]
-one_function_per_file = { max_lines = 16 }
+one_function_per_file = { max_lines = 15 }
 
 [python.coverage]
 fail_under = 100
diff --git a/packages/python/testing-conventions.toml b/packages/python/testing-conventions.toml
index c85cc6cbd..ccb2e635a 100644
--- a/packages/python/testing-conventions.toml
+++ b/packages/python/testing-conventions.toml
@@ -10,7 +10,7 @@
 extra_scope = ["packages/rust/src", "packages/python/src"]
 
 [python]
-one_function_per_file = { max_lines = 16 }
+one_function_per_file = { max_lines = 15 }
 
 # Same floor as the root file, which this lane no longer reads.
 [python.coverage]
diff --git a/packages/ts/testing-conventions.toml b/packages/ts/testing-conventions.toml
index 74af5039e..9f07b4ede 100644
--- a/packages/ts/testing-conventions.toml
+++ b/packages/ts/testing-conventions.toml
@@ -11,7 +11,7 @@
 extra_scope = ["packages/rust/src", "packages/ts/napi"]
 
 [typescript]
-one_function_per_file = { max_lines = 16 }
+one_function_per_file = { max_lines = 15 }
 
 # Same floors as the root file, which this lane no longer reads.
 [typescript.coverage]
diff --git a/plugins/dirsql-plugin-embeddings/testing-conventions.toml b/plugins/dirsql-plugin-embeddings/testing-conventions.toml
index 62de08320..e86a5df2e 100644
--- a/plugins/dirsql-plugin-embeddings/testing-conventions.toml
+++ b/plugins/dirsql-plugin-embeddings/testing-conventions.toml
@@ -3,7 +3,7 @@
 # exemptions, and deliberately no `[e2e] extra_scope` -- this package compiles
 # none of packages/rust/src, so a core change never stales its attestation.
 [python]
-one_function_per_file = { max_lines = 24 }
+one_function_per_file = { max_lines = 10 }
 
 [python.coverage]
 fail_under = 100
diff --git a/testing-conventions.toml b/testing-conventions.toml
index 77adf8373..973b003c5 100644
--- a/testing-conventions.toml
+++ b/testing-conventions.toml
@@ -80,7 +80,7 @@ extra_scope = ["packages/rust/src"]
 # --- Python (scanned: packages/python/dirsql) ------------------------------
 
 [python]
-one_function_per_file = { max_lines = 16 }
+one_function_per_file = { max_lines = 15 }
 
 # Unit-only coverage floor (branch coverage on, matching the prior --cov-branch).
 # The default for a config-less python caller (internals/distcheck); the
@@ -99,7 +99,7 @@ branch = true
 # build_command field), with `rust_toolchain: true` on the caller supplying cargo.
 
 [typescript]
-one_function_per_file = { max_lines = 16 }
+one_function_per_file = { max_lines = 15 }
 
 # Unit-only coverage floor, per vitest metric.
 [typescript.coverage]