diff --git a/docs/development/STRUCTURE.md b/docs/development/STRUCTURE.md
index d56346bec5..6b59404e98 100644
--- a/docs/development/STRUCTURE.md
+++ b/docs/development/STRUCTURE.md
@@ -15,6 +15,7 @@ egg/
 ├── sandbox/                # Sandbox container (untrusted, runs the LLM agent)
 ├── scripts/                # Validation and lint scripts
 ├── shared/                 # Shared Python libraries (used by gateway + sandbox)
+├── skills/                 # Claude Code skills (installed into sandbox at startup)
 ├── tests/                  # Unit tests
 ├── dev                     # Development CLI (setup, lint, test, ci)
 └── README.md
@@ -30,8 +31,9 @@ egg/
 | `integration_tests/` | Integration tests requiring Docker and real containers | CI / local |
 | `orchestrator/` | SDLC pipeline orchestrator: state management, container lifecycle, HITL queue | Orchestrator container |
 | `sandbox/` | Agent environment: Claude Code, tools, entrypoint | Sandbox container |
-| `shared/` | Shared libraries: logging, config, git utilities, centralized constants | All containers |
 | `scripts/` | CI/lint scripts (config validation, import checks, hardcoded port detection, reviewer job name enforcement, LLM API boundary enforcement, model alias enforcement) | CI / local |
+| `shared/` | Shared libraries: logging, config, git utilities, centralized constants | All containers |
+| `skills/` | Claude Code skills (each subdirectory is a skill with `SKILL.md`) | Sandbox container |
 | `tests/` | Test suite | CI / local |
 
 ## Gateway Structure