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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:

  1. Read-first by default
  2. Write only through the propose → validate → apply lifecycle
  3. Enforce approval gates in Guard and Enforce modes
  4. 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

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Last reviewed by @jschuyler