diff --git a/.github/skills/staticphp-build-troubleshooting/references/log-triage.md b/.github/skills/staticphp-build-troubleshooting/references/log-triage.md
index 8c5d07b7..96f5d6a5 100644
--- a/.github/skills/staticphp-build-troubleshooting/references/log-triage.md
+++ b/.github/skills/staticphp-build-troubleshooting/references/log-triage.md
@@ -21,7 +21,7 @@ Default log directory is `log/`, controlled by `SPC_LOGS_DIR`. The important fil
 - `lib.<pkg>.cmake-error.log`: copied CMake error log.
 - `lib.<pkg>.cmake-output.log`: copied CMake output log.
 
-Logs are created when `SPC_ENABLE_LOG_FILE` is true. Old `*.log` files are cleaned unless the preserve-log env is true. Note the current code checks `SPC_PRESERVE_LOG`, while `config/env.ini` and docs mention `SPC_PRESERVE_LOGS`; verify this mismatch when diagnosing log retention behavior.
+Logs are created when `SPC_ENABLE_LOG_FILE` is true. Old `*.log` files are cleaned unless `SPC_PRESERVE_LOG` is set to a truthy value. The code in `src/bootstrap.php` reads `SPC_PRESERVE_LOG` (no trailing S).
 
 ## Terminal Summary
 
diff --git a/AGENTS.md b/AGENTS.md
index 64982189..2292f0a4 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -23,6 +23,7 @@ If your agent does not automatically discover skills from `.github/skills`, read
 - `config/pkg/target`: final build target and virtual target YAML.
 - `config/pkg/tool`: helper tool package YAML.
 - `config/artifact`: standalone artifact YAML for shared or complex sources/binaries.
+- `log/`: build and shell execution logs (`spc.output.log`, `spc.shell.log`, and per-package CMake/config logs); controlled by `SPC_LOGS_DIR` and `SPC_ENABLE_LOG_FILE`.
 - `src/StaticPHP`: framework core: registry loading, config validation, dependency resolution, package install/build pipeline, doctor, toolchains, runtime shell/executors, exceptions.
 - `src/Package`: package-specific build logic registered by PHP attributes.
 - `src/globals`: constants, helper functions, patches, smoke tests, bundled license text.