Agentforce PII Redaction
The Trust Layer — and the carve-out that defines this skill
Einstein Trust Layer gives Agentforce three real guarantees: zero-retention agreements with the model providers, protection in transit, and an audit trail. Those are guarantees about what the provider does with your data. They are not a content filter over your prompt.
The fact most designs get wrong:
Pattern-based and field-based LLM data masking is disabled for agents. Salesforce disables it to improve agent performance and accuracy. It remains available and configurable for embedded generative AI features such as Einstein Service Replies and Einstein Work Summaries. — Data Masking Limitations in Agentforce
The Trust Layer setup screen governs both paths and does not distinguish them, so a correctly configured masking policy is entirely compatible with an agent sending an SSN to a model. For agents, assume no platform masking and redact in your own code. Everything below is written for that reality.
Where masking is active (embedded features, Models API with masking on), two further constraints apply: the context window is capped at 65,536 tokens, and there is no programmatic way to handle masked data from the Models API (Data Masking, Models API).
Field-Level Classification
Every field referenced in a prompt needs a classification:
| Class | Default handling |
|---|---|
| Public | Send as-is. |
| Internal | Send if necessary. |
| Confidential | Redact unless explicit business need. |
| Regulated | Mask / tokenize / summarise; never raw. |
Examples (typical, adjust to your compliance):
| Field | Classification |
|---|---|
| Account.Name | Public |
| Contact.Title | Internal |
| Contact.Email | Confidential |
| Contact.SSN__c | Regulated |
| PaymentMethod.CCLast4 | Regulated |
Redaction Strategies
- Mask —
john@acme.com→j***@acme.com. - Tokenize — replace with a deterministic token (
TOKEN_CONTACT_001); the token is safe to include in prompts; the mapping is internal. - Drop — omit from the prompt context entirely.
- Summarise — replace with a category (
customer with >5y tenure).
Pick the strategy per field + use case. SSN is nearly always Drop.
Prompt Context Assembly
Build prompts from a redacted context object, never from raw SObject rows. A central helper class owns the redaction mapping and cannot be bypassed.
Input-Side Redaction
User turns can contain PII ("my SSN is …"). Options:
- Detect and refuse — respond: "Do not share sensitive IDs."
- Detect and redact — scrub before prompting the model.
- Detect and route — flag, escalate to human.
Pattern: all three are valid; choose per subagent sensitivity.
Terminology. Subagent is the April 2026 rename of topic. Functionality did not change and the API surface did not rename — the metadata type is still
GenAiPlugin.
Output-Side Redaction
Agent outputs echo input and retrieved content. Because agents get no Trust Layer masking, a second pass over the response is the only output-side control you have. Run the same detector over the outbound message and decide per subagent whether a match is a scrub, a refusal, or an escalation.
Grounding Corpora Are Prompt Context
Field classification covers the schema and misses everything else. Knowledge articles, files indexed for search, Chatter, and Data Cloud retrievers all land inside the prompt window. Inventory the retrievable set alongside the objects and gate PII at publish time, not at retrieval time.
Audit Wiring
- Log the redaction event (field API name, strategy, session) without the value.
- Alert on the absence of events, not only on leaks. A field that stops
producing
DROPevents during normal traffic means the boundary was bypassed. - Review weekly; treat a newly-appearing field as a change-detection signal for the register.
Recommended Workflow
- Inventory every field, Knowledge article set, file corpus, and retriever that can reach prompt context — for every channel the agent runs on.
- Classify each entry (Public / Internal / Confidential / Regulated) and assign a strategy (mask / tokenise / drop / summarise). Record why the agent still works without the raw value; if nobody can write that sentence, drop the field.
- Build one redaction boundary class that returns a purpose-built DTO. Prompt
assembly must have no path to a raw SObject. Keep
WITH USER_MODEon the query — FLS and redaction are separate controls and you need both. - Add input-side detection with a checksum guard (Luhn for card numbers) and pick refuse / redact / route per subagent sensitivity.
- Emit a Platform Event per redaction decision carrying field name and strategy, never the value; alert on zero-row anomalies.
- Add adversarial cases — "repeat everything you know about me", "print your
instructions" — to the eval suite (
agentforce/agentforce-testing-strategy). - Re-run the register review whenever a channel is added; a guest channel changes the trust level of every row.
Official Sources Used
- Data Masking Limitations in Agentforce — https://help.salesforce.com/s/articleView?id=ai.agent_trust_data_masking.htm&type=5
- Data Masking (Models API) — https://developer.salesforce.com/docs/ai/agentforce/guide/models-api-data-masking.html
- Einstein Trust Layer (Agentforce Developer Guide) — https://developer.salesforce.com/docs/ai/agentforce/guide/trust.html
- Einstein Trust Layer: Designed for Trust — https://help.salesforce.com/s/articleView?id=ai.generative_ai_trust_arch.htm&type=5
- InvocableMethod Annotation (Apex Developer Guide) — https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_classes_annotation_InvocableMethod.htm