diff --git a/context-action/action.yml b/context-action/action.yml
new file mode 100644
index 0000000..3510e5d
--- /dev/null
+++ b/context-action/action.yml
@@ -0,0 +1,69 @@
+name: 'Nullify Context'
+description: 'Upload context data (Terraform plans, CI logs, etc.) to Nullify for infrastructure-aware security analysis'
+branding:
+  icon: 'upload-cloud'
+  color: 'blue'
+
+inputs:
+  nullify-token:
+    description: 'Nullify service account JWT'
+    required: true
+  type:
+    description: 'Context type: terraform, ci_logs, config, deploy, api_spec'
+    required: true
+  name:
+    description: 'Logical name for this context. Auto-derived from file path if omitted (e.g. infrastructure/networking/plan.json → infrastructure/networking)'
+    required: false
+    default: ''
+  mode:
+    description: 'Upload mode: merge-only, pr-only, both'
+    default: 'both'
+  environment:
+    description: 'Deployment environment: development, staging, production, unknown'
+    default: 'unknown'
+  plan-path:
+    description: 'Path to the file(s) to upload. Supports glob patterns. Defaults to **/plan.json'
+    default: ''
+  skip-on-draft:
+    description: 'Skip upload for draft PRs'
+    default: 'true'
+  dry-run:
+    description: 'Log what would be uploaded without uploading'
+    default: 'false'
+
+outputs:
+  action-taken:
+    description: 'Action taken: uploaded, skipped, cleaned-up'
+    value: ${{ steps.run.outputs.action_taken }}
+  upload-path:
+    description: 'S3 key prefix where data was uploaded'
+    value: ${{ steps.run.outputs.upload_path }}
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Install Nullify CLI
+      shell: bash
+      run: |
+        if command -v nullify &>/dev/null; then
+          echo "Nullify CLI already installed: $(nullify --version 2>/dev/null || echo 'unknown')"
+        else
+          curl -sSL https://cli.nullify.ai/install.sh | bash || {
+            echo "::error::Failed to install Nullify CLI"
+            exit 1
+          }
+        fi
+
+    - name: Run context action
+      id: run
+      shell: bash
+      env:
+        NULLIFY_TOKEN: ${{ inputs.nullify-token }}
+        INPUT_TYPE: ${{ inputs.type }}
+        INPUT_NAME: ${{ inputs.name }}
+        INPUT_MODE: ${{ inputs.mode }}
+        INPUT_ENVIRONMENT: ${{ inputs.environment }}
+        INPUT_PLAN_PATH: ${{ inputs.plan-path }}
+        INPUT_SKIP_ON_DRAFT: ${{ inputs.skip-on-draft }}
+        INPUT_DRY_RUN: ${{ inputs.dry-run }}
+      run: ${{ github.action_path }}/scripts/entrypoint.sh
diff --git a/context-action/scripts/entrypoint.sh b/context-action/scripts/entrypoint.sh
new file mode 100755
index 0000000..c608acb
--- /dev/null
+++ b/context-action/scripts/entrypoint.sh
@@ -0,0 +1,144 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# ============================================================
+# Nullify Context Action — Entrypoint
+# Determines what action to take based on GitHub event context
+# and mode, then invokes the Nullify CLI.
+# ============================================================
+
+ACTION_TAKEN="skipped"
+
+# --- Detect event context ---
+EVENT_NAME="${GITHUB_EVENT_NAME:-}"
+REF_NAME="${GITHUB_REF_NAME:-}"
+PR_NUMBER=""
+PR_MERGED="false"
+PR_DRAFT="false"
+PR_ACTION=""
+
+if [[ "$EVENT_NAME" == "pull_request" ]]; then
+  PR_NUMBER=$(jq -r '.pull_request.number // empty' "$GITHUB_EVENT_PATH" 2>/dev/null || true)
+  PR_MERGED=$(jq -r '.pull_request.merged // false' "$GITHUB_EVENT_PATH" 2>/dev/null || echo "false")
+  PR_DRAFT=$(jq -r '.pull_request.draft // false' "$GITHUB_EVENT_PATH" 2>/dev/null || echo "false")
+  PR_ACTION=$(jq -r '.action // empty' "$GITHUB_EVENT_PATH" 2>/dev/null || true)
+fi
+
+echo "Event: $EVENT_NAME | Mode: $INPUT_MODE | Ref: $REF_NAME | PR: ${PR_NUMBER:-none}"
+
+# --- Skip on draft PRs ---
+if [[ "$INPUT_SKIP_ON_DRAFT" == "true" && "$PR_DRAFT" == "true" ]]; then
+  echo "Skipping — draft PR"
+  echo "action_taken=skipped" >> "$GITHUB_OUTPUT"
+  exit 0
+fi
+
+# --- Mode decision matrix ---
+should_upload="false"
+should_cleanup="false"
+
+case "$INPUT_MODE" in
+  merge-only)
+    if [[ "$EVENT_NAME" == "push" ]]; then
+      should_upload="true"
+    fi
+    ;;
+  pr-only)
+    if [[ "$EVENT_NAME" == "pull_request" ]]; then
+      if [[ "$PR_ACTION" == "closed" ]]; then
+        should_cleanup="true"
+      elif [[ "$PR_ACTION" == "opened" || "$PR_ACTION" == "synchronize" ]]; then
+        should_upload="true"
+      fi
+    fi
+    ;;
+  both)
+    if [[ "$EVENT_NAME" == "push" ]]; then
+      should_upload="true"
+    elif [[ "$EVENT_NAME" == "pull_request" ]]; then
+      if [[ "$PR_ACTION" == "closed" ]]; then
+        should_cleanup="true"
+      elif [[ "$PR_ACTION" == "opened" || "$PR_ACTION" == "synchronize" ]]; then
+        should_upload="true"
+      fi
+    fi
+    ;;
+  *)
+    echo "::error::Invalid mode: $INPUT_MODE (must be merge-only, pr-only, or both)"
+    exit 1
+    ;;
+esac
+
+# --- Execute ---
+if [[ "$should_upload" == "true" ]]; then
+  # Resolve files to upload
+  PLAN_PATH="${INPUT_PLAN_PATH:-}"
+  if [[ -z "$PLAN_PATH" ]]; then
+    # Default: find all plan.json files recursively
+    PLAN_PATH="**/plan.json"
+  fi
+
+  # Expand glob into array safely
+  shopt -s nullglob globstar
+  FILES=()
+  for f in $PLAN_PATH; do
+    FILES+=("$f")
+  done
+  shopt -u nullglob globstar
+
+  if [[ ${#FILES[@]} -eq 0 ]]; then
+    echo "::warning::No files matched pattern: $PLAN_PATH"
+    echo "action_taken=skipped" >> "$GITHUB_OUTPUT"
+    exit 0
+  fi
+
+  echo "Found ${#FILES[@]} file(s) to upload"
+
+  # Upload each file as a separate context entry with name derived from path
+  for f in "${FILES[@]}"; do
+    # Derive name from file's parent directory
+    # e.g. infrastructure/networking/plan.json → infrastructure/networking
+    # e.g. plan.json → root
+    FILE_DIR=$(dirname "$f")
+    if [[ "$FILE_DIR" == "." || "$FILE_DIR" == "/" ]]; then
+      FILE_NAME="root"
+    else
+      FILE_NAME="$FILE_DIR"
+    fi
+
+    # Use explicit --name if provided, otherwise use derived name
+    EFFECTIVE_NAME="${INPUT_NAME:-$FILE_NAME}"
+
+    # Build CLI args as array (prevents command injection)
+    CLI_ARGS=(
+      "--type" "$INPUT_TYPE"
+      "--name" "$EFFECTIVE_NAME"
+    )
+
+    if [[ -n "${INPUT_ENVIRONMENT:-}" ]]; then
+      CLI_ARGS+=("--environment" "$INPUT_ENVIRONMENT")
+    fi
+
+    if [[ -n "$PR_NUMBER" && "$EVENT_NAME" == "pull_request" ]]; then
+      CLI_ARGS+=("--pr-number" "$PR_NUMBER")
+    fi
+
+    if [[ "${INPUT_DRY_RUN:-false}" == "true" ]]; then
+      CLI_ARGS+=("--dry-run")
+    fi
+
+    echo "Uploading: $f (name=$EFFECTIVE_NAME)"
+    nullify api context push "${CLI_ARGS[@]}" "$f"
+  done
+
+  ACTION_TAKEN="uploaded"
+
+elif [[ "$should_cleanup" == "true" ]]; then
+  echo "PR #${PR_NUMBER} closed — cleanup would happen here (not yet implemented)"
+  ACTION_TAKEN="cleaned-up"
+
+else
+  echo "No action needed for event=$EVENT_NAME mode=$INPUT_MODE"
+fi
+
+echo "action_taken=$ACTION_TAKEN" >> "$GITHUB_OUTPUT"