Clarify test data config for validator test data

Author: niemela

spec/2023-07-draft.md

@@ -664,10 +664,12 @@ Their goal is to ensure the integrity and quality of the test data and validatio
 
 #### Invalid Input
 
-The files under `invalid_input`  are invalid inputs.
+The files under `invalid_input` are invalid inputs.
 Unlike in `sample` and `secret`, there are no `.ans` files.
 Each `tc.in` under `invalid_input` must be rejected by at least one input validator.
 
+The relevant settings from [Test Case Configuration](#test-case-configuration) (`input_validator_args`, and `description`) can be set in `tc.yaml` for one test case, or `test_group.yaml` for all test cases in the same directory.
+
 #### Invalid Output
 
 The test cases in `invalid_output` describe invalid outputs for non-interactive problems.
@@ -681,7 +683,7 @@ In particular, for any test case in `invalid_output/`, for example `invalid_outp
 <output_validator_program> tc.in tc.ans dir [arguments] < tc.out # MUST FAIL
 ```
 
-The directory `invalid_output` must be organized into a tree-like structure similar to `secret` and may contain arguments in `test_group.yaml` files that are passed to the validators.
+The relevant settings from [Test Case Configuration](#test-case-configuration) (`input_validator_args`, `output_validator_args`, and `description`) can be set in `tc.yaml` for one test case, or `test_group.yaml` for all test cases in the same directory.
 
 ### Valid Output
 
@@ -698,7 +700,7 @@ In particular, for any test case in `valid_output/`, for example `valid_output/t
 <output_validator_program> tc.in tc.ans dir [arguments] < tc.out # MUST PASS
 ```
 
-The directory `valid_output` must be organized into a tree-like structure similar to `secret` and may contain arguments in `test_group.yaml` files that are passed to the validators.
+The relevant settings from [Test Case Configuration](#test-case-configuration) (`input_validator_args`, `output_validator_args`, and `description`) can be set in `tc.yaml` for one test case, or `test_group.yaml` for all test cases in the same directory.
 
 ### Samples