AI Safety
·IdenticAPI

When Should an AI Response Be Blocked vs Sent for Review?

Define when to block AI output outright vs route it for human review — verdict semantics, risk levels, and workflow design.

An AI response should be blocked when automated screening indicates high-confidence harm, executable markup, or clear policy violations that must not reach users — and sent for human review when signals are ambiguous, context-dependent, or severity is medium, where a trained reviewer can approve, edit, or reject without exposing raw flagged text to the end user.

There is no universal rule for every product; you define thresholds on top of IdenticAPI safe, suspicious, and unsafe verdicts. This guide helps you design those policies with comparison tables and workflow patterns.

Verdict semantics (IdenticAPI)

AI Output Safety returns structured results from:

curl -X POST https://www.identicapi.com/api/v1/security/output-safety \
  -H "Authorization: Bearer idapi_test_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{"text": "Assistant message to evaluate"}'

Key fields:

FieldMeaning
verdictsafe, suspicious, or unsafe
riskSeverity hint (e.g., low, medium, high)
findingsCategorized reasons
reasonsHuman-readable explanation list

Verdicts are risk signals, not legal judgments or guarantees. Your policy maps them to block, review, or allow. Full schema: documentation.

Block vs review vs allow

ActionWhen to useUser seesInternal handling
Allow (deliver)safe verdict; content passes rendering controlsNormal assistant replyLog metadata optional
Reviewsuspicious verdict; borderline policy; novel phrasingGeneric holding message or delayed replyQueue with context for human
Blockunsafe verdict; high risk; executable markup; disallowed categoriesStatic safe fallback onlyDo not echo flagged text

Default posture for unknown failures: fail closed (block or review) rather than delivering unmoderated LLM output — see improper output handling.

Decision matrix by finding category

Use API findings[].category plus your product context:

Category (illustrative)Typical verdictRecommended actionRationale
Unsafe markup (script, event handlers)unsafeBlockXSS and injection risk if rendered
Deceptive / phishing patternsunsafeBlockUser harm, brand damage
Harassment or threatsunsafeBlockSafety and policy
Sexual content (non-consent contexts)unsafeBlockAudience policy
Medical/legal/financial advice (restricted products)suspiciousunsafeReview or BlockContext-dependent liability
Mild profanity in adult productsuspiciousReview or allow with rulesBrand dependent
Technical docs mentioning "kill process"suspiciousReview or Allow after sanitizerFalse positive prone
Benign formatting HTML (allowlisted tags)safeAllow after sanitizerDefense in depth still applies

Tune rows for your audience — developer docs vs consumer support bots differ sharply.

Block workflow

When action is block:

  1. Replace assistant output with pre-approved fallback text
  2. Log request_id, verdict, categories — not necessarily full text in production logs
  3. Optionally increment abuse counters for session monitoring
  4. Do not show the model's unsafe reply "for debugging" to end users

Example fallback:

"I can't provide that response. Please rephrase or contact support."

Blocking patterns: How to Moderate LLM Output, real-time chat.

Review workflow

When action is review:

  1. Customer/user sees a neutral message ("Thanks — a team member will follow up") — not flagged content
  2. Review queue stores: user prompt (redacted), model output (access-controlled), findings, timestamp
  3. Reviewer options: approve edited version, reject with template, escalate
  4. SLA targets defined by team (support vs public social)

Review is appropriate when:

  • Verdict is suspicious but not clearly malicious
  • High-value transactions mentioned (refunds, credits) — support bot guide
  • Regulatory language requires human approval
  • New model version increases suspicious rate temporarily

Avoid review queues as dumping grounds — if >30% of traffic lands in review under synthetic tests, tune policies before launch (threshold is guidance for testing, not an industry stat).

Comparison: block-first vs review-first products

FactorBlock-firstReview-first
User experienceMore refusalsMore delays / handoffs
Safety marginHigherDepends on reviewer capacity
Best forPublic consumer chat, HTML renderingEnterprise support, regulated workflows
Operational costLower staffingRequires reviewer tooling
False positive impactHigher user frictionHigher reviewer load

Many teams use block for unsafe and review for suspicious — a hybrid default.

Risk level overlay

Combine verdict with risk when provided:

verdictriskSuggested routing
unsafehighBlock
unsafemediumBlock (or review if niche false positives documented)
suspicioushighReview (or block for strict products)
suspiciouslowReview or allow with logging
safeanyAllow after rendering pipeline

Document overrides in version-controlled policy config, not scattered if statements.

Streaming and partial output

Block/review decisions apply to the assembled message. Do not deliver stream chunks to the DOM before final verdict — partial bypass splits payloads across tokens. Buffer server-side, then route.

Unified Guard and multiple detectors

When using Unified Guard with multiple checks, define precedence:

  • Any unsafe from output safety → block
  • Conflicting signals → conservative route (review or block)
  • Compare orchestration vs single-purpose moderation in AI Guardrails vs Content Moderation

Metrics to track

MetricPurpose
Block rateDetect model/policy drift
Review queue depthStaffing
Approval vs rejection in reviewTune suspicious handling
Top finding categoriesTargeted tests
Time-to-deliver for allowed messagesLatency budget

Prototype category distribution with the AI Output Safety Checker.

Anti-patterns

  1. Showing flagged text with a warning banner — Users still exposed; attackers still benefit
  2. Review without access control — Leaks sensitive flagged content internally
  3. Auto-approve review after timeout — Converts review into delay-only block
  4. Different policies per client — Mobile bypasses web moderation
  5. Blocking user messages but never assistant outputInput vs output gap

Testing policy before launch

Synthetic corpus:

  • Clearly malicious → must block
  • Borderline technical → expect review or allow per your doc
  • Benign FAQ → must allow

Automate in CI; manual review weekly on sampled suspicious production cases.

Implementation references

Limitations

Automated verdicts cannot capture full business context:

  • Legal interpretations vary by jurisdiction
  • Brand voice allows edgy content in some products and not others
  • Humans remain accountable for final decisions in high-stakes review

Use safe / suspicious / unsafe as inputs to a documented policy — block when harm is clear, review when judgment is required, and never deliver unmoderated output when checks fail.

Frequently asked questions

When should I block an AI response instead of reviewing it?

Block when the verdict is unsafe, risk is high, or findings indicate executable markup, threats, phishing patterns, or clear policy violations that must not reach users under any circumstance.

When is human review appropriate?

Review suspicious verdicts, context-dependent policy topics, high-value transactions, or borderline technical language where false positives are likely and a trained reviewer can approve or edit safely.

Should users ever see flagged model text with a warning label?

No. Warning banners still expose harmful or executable content. Replace blocked or pending-review outputs with static safe messaging.

What is a practical default mapping for IdenticAPI verdicts?

Many products deliver on safe, queue suspicious for review with a neutral user message, and block unsafe with a fallback. Document overrides in version-controlled policy config.

Do block and review decisions apply to streaming partials?

Apply decisions to the assembled message. Do not deliver unmoderated stream chunks to the DOM; buffer server-side before routing verdicts.

Related reading