Require nonblank notification identities

docs/config.md

@@ -135,6 +135,9 @@ Distributor notification is disabled by default. Its fields are:
 The upload token is read from the environment variable named by `token_env`.
 Use `secrets.directory` when a file-backed secret is appropriate.
 
+When notification is enabled, each rendered single-report pipeline ID, bundle
+ID, and idempotency key must contain at least one non-whitespace character.
+
 Single-report bundle templates accept `location_id`, `report_id`, `run_id`,
 `artifact_group`, `batch_output_name`, `valid_start_date`, `valid_end_date`,
 `valid_start_time`, `valid_end_time`, `valid_start_stamp`, `valid_end_stamp`,

docs/integrations/distributor/api.md

@@ -23,8 +23,8 @@ A successful response is `202 Accepted` with JSON containing `run_id` and
 `status`. Acceptance means Distributor staged and validated the source bundle;
 it does not mean downstream destinations have published it.
 
-The adapter requires a pipeline ID, bundle ID, idempotency key, and at least one
-source-file mapping before calling Distributor. It reads the bearer token from
+The adapter requires nonblank pipeline ID, bundle ID, and idempotency key, plus
+at least one source-file mapping, before calling Distributor. It reads the bearer token from
 the configured environment variable and redacts that value from errors. Request
 construction and timeout handling belong to the [Distributor adapter](../../internal/distributor-adapter.md).
 

docs/operations.md

@@ -69,6 +69,8 @@ returns a failed batch status even when all report counters show success; the
 top-level notification result contains the delivery diagnostic.
 
 For a single report, Distributor notification follows the atomic output write.
+Enabled notification templates are validated before report processing, including
+the requirement that each rendered identity contains a non-whitespace character.
 See the [configuration reference](config.md) for pipeline, bundle,
 idempotency-key, and per-report path templates.