Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add rules/ekakit/lightfast-mcp/config-validation-workflowgit clone --depth 1 https://github.com/ekakit/lightfast-mcpWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00879 |
| Opus 5 | $0.00000 | $0.00439 |
| Sonnet 5 | $0.00000 | $0.00176 |
| Haiku 4.5 | $0.00000 | $0.00088 |
Grade A, and why
config-validation-workflow scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Configuration Validation Workflow
When editing configuration files, execute these validation steps immediately:
Immediate Actions After Config Changes
- Validate Syntax: Check YAML/JSON syntax is valid
- Test Configuration Loading: Verify config can be loaded by the application
- Validate Schema: Ensure required fields are present
- Test Server Startup: Verify servers can start with new configuration
Automatic Validation Commands
YAML Configuration Files
# Validate YAML syntax
python -c "import yaml; yaml.safe_load(open('{current_file}'))"
# Test configuration loading
uv run python -c "from tools.orchestration.config_loader import ConfigLoader; ConfigLoader().load_servers_config('{current_file}')"
# Test server startup with new config
uv run lightfast-mcp-orchestrator list
JSON Configuration Files
# Validate JSON syntax
python -c "import json; json.load(open('{current_file}'))"
# For MCP configuration files
if [[ "{current_file}" == *"mcp.json"* ]]; then
echo "MCP config updated - restart Cursor to reload"
fi
Configuration File Validation Checklist
Server Configuration (config/servers.yaml)
- All servers have required fields: name, description, host, port, transport
- Port numbers don't conflict (8001=Blender, 8002=Mock, 8003+=Others)
- Transport types are valid: "stdio" or "streamable-http"
- Server types match registered server types
- Environment variables are properly formatted
MCP Configuration (.cursor/mcp.json)
- Server commands use proper paths
- Environment variables are correctly set
- Working directories exist (for global configs)
- Server names are unique
Test Configuration Changes
After Editing Server Config
# Test configuration loading
uv run lightfast-mcp-orchestrator list
# Test server startup
uv run lightfast-mcp-orchestrator start --hide-logs &
sleep 5
pkill -f lightfast-mcp-orchestrator
# Validate no port conflicts
netstat -an | grep -E ':(8001|8002|8003|8004|8005)\s'
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 127 lines · 0 tokens per session scan A 84a1bc12f06c
config-validation-workflow is a cursor rule published in the GitHub repository ekakit/lightfast-mcp (2 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 879 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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