Presenter view

Decision architecture speaker notes

Explain how Praxis narrows a large panel, gives stateless agents trusted context, escalates model effort only when necessary and keeps consequential action behind a clinician.

Opening cue

“The previous layer gave Praxis a trustworthy longitudinal patient state. This layer decides whether that change deserves attention, which specialists should reason about it and how it should compare with work across the rest of the panel.”

01 · Decision boundary + panel funnel

Do cheap work broadly; expensive reasoning selectively

“The input is an updated longitudinal patient state. The output is either NoAction or a versioned DecisionCandidate. A candidate is not an executed clinical action—it is an explainable proposal that can enter a durable approval workflow.”

Panel request example

1,200

rule-scored

30

candidates

8

fresh reasoning

How to walk the control flow

  1. 01

    Freeze the panel and patient-state versions.

  2. 02

    Run safety overrides, eligibility rules and deterministic scores.

  3. 03

    Reuse fresh candidates; identify missing, stale or conflicting reasoning.

  4. 04

    Build context, route specialists, reconcile, ground and rank.

Key point: a clinician request does not create 1,200 agent sessions. Most patients stop after deterministic computation, and already-fresh candidates are reused.

02 · Context Builder

Longitudinal state becomes task-specific memory

Clinical memory

PostgreSQL

Current snapshot, personal baselines, longitudinal trends, active conditions and open care gaps.

Evidence memory

pgvector + text search

Notes, reports, messages and source-linked document chunks.

Workflow memory

PostgreSQL + Temporal

Previous recommendations, approvals, rejections, completed actions and current execution state.

Preference memory

PostgreSQL

Explicit clinician communication, routing and workflow preferences—separate from clinical truth.

Knowledge memory

Versioned knowledge store

Approved clinical guidelines and organization policies with effective dates and versions.

ContextPacket

“Agents are stateless. The Context Builder gives each one a frozen, versioned packet containing only the relevant slice of patient history, evidence, prior workflow outcomes, explicit preferences and approved knowledge.”

context_idpatient_idworkflow_idtriggeras_ofstate_versionrelevant_changelongitudinal_windowevidence_citationsguideline_versionsprior_outcomespreferencesmissing_or_conflicting_dataallowed_toolsrisk_leveltoken_budgetexpires_at
The longitudinal record stores baseline, trends, episodes, prior recommendations and outcomes. Temporal stores workflow progress. Neither is hidden inside an agent conversation.

03 · Agents, directory + tools

Logical roles in one governed runtime

Agent roster

Ten registered roles; usually two to five run.

01

Clinical Coordinator

Optional

Scopes complex or ambiguous multi-condition reasoning.

02

Diabetes & Metabolic

Specialist

Reviews metabolic trends, care gaps and related complications.

03

Cardiovascular

Specialist

Reviews cardiovascular changes and relevant longitudinal risk.

04

Kidney

Specialist

Reviews renal trends, gaps and cross-condition implications.

05

Medication Safety

Specialist

Reviews medication changes, monitoring and interactions.

06

Preventive Care

Specialist

Reviews screening, vaccination and preventive gaps.

07

Reconciler

Shared

Combines compatible assessments and preserves unresolved conflicts.

08

Grounding Reviewer

Shared

Verifies claims, citations, freshness and guideline support.

09

Inbox Drafting

Workflow

Converts a validated decision into a reviewable response draft.

10

Practice Improvement

Workflow

Finds practice-level patterns from governed aggregate evidence.

Agent Directory

“This is a registry of approved, versioned agent manifests: supported triggers, context schema, allowed tools, model policy, risk class, budgets, prompt version and evaluation suite. The router selects from this registry; it does not invent agents.”

Draft
Eval
Shadow
Canary
Active
Disabled

Tool Gateway

Each agent sees only four to eight typed tools needed for its task. Tenant and patient scope come from the workflow—not model arguments. There is no arbitrary SQL.

Patient state

Read

snapshot · timeline · labs · medications · care gaps · prior outcomes

Evidence

Read

document search · message thread · source chunk · citation resolver

Knowledge

Read

guideline search · approved section · organization policy

Calculations

Compute

approved measure · personal baseline · trend · interaction check

Preparation

Prepare

message draft · task draft · order request · EHR note draft

Execution

Approval only

send message · create task · submit order · write note

Simple delegation example

“The Kidney Agent can call a scoped tool for a missing renal trend. If it believes Medication Safety is needed, it returns a typed SpecialistRequest. The router checks relevance, duplication, risk and budget, then Temporal starts that specialist. The agent never directly creates another agent.”

Maximum depth one · maximum three specialists · no recursive spawning

04 · Model routing + ranking

Complexity chooses the model; risk chooses the safeguards

Tier 0

No model

Rules, calculations, safety gates and ranking

Deduplicate an event, compare to baseline and score the panel.

0 tokens

Tier 1

Small model

Classification and extraction

Extract symptom, timing and likely specialty from an ambiguous message.

≤ 2k in · 150 out

Tier 2

Mid-tier model

Normal specialist reasoning, drafting and grounding

Assess one condition using relevant trends, evidence and guidelines.

≤ 8–12k in · 1.2k out

Tier 3

Frontier model

Complex multi-condition reconciliation

Resolve conflicting specialists across a long, contradictory timeline.

≤ 24k in · 1.5k out

Initial priority hypothesis

Explainable 0–100 score

Potential clinical severity30%
Change from personal baseline25%
Time sensitivity20%
Unresolved work15%
Actionability10%
“Safety overrides run before ranking. Confidence and freshness stay separate from priority, so missing information cannot quietly push a serious case down the list. Before activation, I compare the candidate’s dependency versions with the latest patient state.”

Freshness rule

A new relevant lab, medication change, message or completed action invalidates the affected candidate. Temporal reruns only the dependent steps; unrelated events do not discard useful work.

05 · Worked escalation + human loop

New lab plus dizziness after a medication change

01Ingestion

Two new signals

A new lab result arrives and the patient reports dizziness after a medication change.

02Tier 0

Deterministic gate

Verify identity, update longitudinal state, compare to baseline and apply critical-event policy.

03Tier 1

Classify ambiguity

Extract symptom, timing and the likely kidney + medication-safety specialties from the message.

04Context

Build shared context

Load renal trend, medication timeline, prior actions, approved guidance and exact citations.

05Tier 2

Reason in parallel

Kidney and Medication Safety Agents independently produce typed, cited assessments.

06Tier 3

Escalate conflict

If assessments materially disagree, frontier reconciliation resolves what it can and preserves uncertainty.

07Human gate

Validate and approve

Ground every claim, apply safety policy and present evidence, conflicts and missing data to the clinician.

08

Clinician chooses

Approve, edit, reject, request more data or escalate.

“The lab is handled deterministically first. A small model extracts symptom and timing from the message. Kidney and Medication Safety reason independently. If they materially disagree, the Reconciler may use the frontier tier. The Grounding Reviewer then checks every claim and citation before the clinician sees it.”

Conflict behavior

Typed specialist outputs make overlap and disagreement visible. A deterministic pre-merge combines compatible claims. One reconciliation and grounding revision is allowed; unresolved material conflict becomes a human-review reason, not a fabricated consensus.

06 · Reliability, evaluation + assumptions

Every failure becomes an explicit state

Failure behavior

Transient tool failure

Retry with backoff and the same idempotency key.

Invalid model output

One schema repair; then approved same-tier fallback.

Required specialist fails

Stop completion and route to human review.

Context becomes stale

Reject activation and rerun only the affected steps.

Grounding fails

One revision cycle; then human escalation.

Worker crashes

Temporal resumes from recorded workflow state.

Evaluation stack

Deterministic unit tests

routing · scores · freshness · policies · idempotency

Tool contract tests

schemas · scope · permissions · timeouts · citations

Agent evaluation suites

correctness · abstention · grounding · calibration · cost

Multi-agent tests

agreement · conflicts · partial failure · unsupported synthesis

Workflow replay tests

crashes · duplicate events · cancellation · late approval

Deployment gates

offline → replay → shadow → clinician review → canary

Say this explicitly

“The weights, thresholds, funnel sizes, freshness windows, agent limits, model tiers and token budgets shown here are starting hypotheses—not clinical truth. I would version and tune them through offline evaluations, historical replay, shadow mode, clinician review and canary rollout.”

Priority-score weights and tier boundaries
Critical-event and approval policies
Panel funnel sizes and maximum three specialists
Candidate expiration and invalidation rules
Model assignment, token budgets and escalation thresholds
Latency, cost and confidence targets

Closing transition

“At this point Praxis has decided what deserves attention and produced an evidence-backed, versioned candidate. The next architecture question is how Temporal coordinates approval, waiting, retries and execution across hours or days.”