Read vs. write surfaces
preset AI is bi-directional infrastructure: AI tools can both read and write through MCP. Clear boundaries between the two prevent policy bypass and unsafe auto-apply behavior.
Why this matters
Without explicit read/write boundaries:
- Policy gates can be bypassed by treating writes as routine
- Auto-apply becomes the default and drift accumulates silently
- Auditability degrades — you lose the trail of who changed what
Read surfaces
Read surfaces gather context and should be the default mode of operation.
Use for:
- Artifact discovery
- Token, preset, and pattern lookup
- Active constraint retrieval
- Health, drift, and compliance diagnostics
Properties:
- No canonical state mutation
- Low operational risk
- High frequency in normal workflows
Write surfaces
Write surfaces can mutate system state directly or indirectly.
Use for:
- Creating or updating proposals
- Applying approved changes
- Mutating canonical artifacts
Properties:
- Governance policy applies
- Requires explicit scope and permissions
- Must be auditable
Guardrail policy
Recommended baseline for any client integrating against MCP:
- Read-first by default
- Write only through the propose → validate → apply lifecycle
- Enforce approval gates in Guard and Enforce modes
- Always log actor, scope, diff metadata, and outcome
When to escalate
Treat a write as elevated risk — request additional approval or surface the action to the user — when:
- The change impacts shared artifacts broadly
- Policy-critical rules are affected
- Confidence is low or validation findings are ambiguous
Last reviewed by @jschuyler