Interview
Sierra AI FDE interview guide
Sierra Forward Deployed / Agent Engineer loops test whether you can land customer-facing agents inside real enterprise workflows — tool permissions, escalation paths, evals, and adoption — not chat demos alone.
Agent platforms amplify both value and blast radius. Interviewers listen for whether you design containment first — then expand autonomy with evidence.
Interview loop matrix
| Stage | What they probe | Format | Pass signal |
|---|---|---|---|
| Recruiter screen | Coding bar, travel, customer vs platform mix | 30–45 min call | You frame in-account agent outcomes, not slide decks |
| Technical / coding screen | APIs, state machines, debugging, production taste | Timed or live | Clean interfaces under incomplete specs |
| Agent design deep dive | Tools, memory, escalation, audit logs | Design + critique | Least privilege + human gates on irreversible actions |
| Customer workflow case | Scoping, thin slice, integrations, adoption | Ambiguous scenario | One measurable workflow with promotion gates |
| Evals & reliability | Task success, safety, latency, cost | Design discussion | Golden tasks before wider autonomy |
| Behavioral / HM | Conflict, exec updates, ownership under ambiguity | Story-driven | Honest failure modes; clear next unlock |
Grading rubric
| Dimension | Strong | Weak |
|---|---|---|
| Containment | Least privilege tools, kill switch, audit trail | Unrestricted tool calling for demo speed |
| Workflow realism | Maps agent steps to an existing customer SOP | Invented greenfield process nobody owns |
| Eval discipline | Task success + safety gates before expanding autonomy | Fluent chat as proof of readiness |
| Integration taste | Idempotent writes, retries, and failure surfacing | Fire-and-forget CRM updates |
| Scope control | One persona / one workflow / one KPI | Company-wide agent mesh in phase one |
| Communication | Precise risk language to security and ops owners | Hand-waves blast radius |
Red flags
- No human gate on tools that mutate systems of record
- No eval pack of golden customer tasks
- Ignoring identity and audit requirements
- Cannot define Day-2 ownership after go-live
Practice scenarios
- Support agent can refund orders and open tickets — design permissions and escalation.
- Agent quality is good on happy path; it loops on edge cases — what instrumentation and gates do you add?
- Security blocks write access until review — what thin slice still ships value in 30 days?
Pair with agent evals, decomp simulator, Glean FDE, and Harvey FDE.
7-day prep plan
- Day 1–2 — Coding + tool-calling agent sketch with gates
- Day 3 — Eval harness for task success + safety
- Day 4 — Full customer workflow case
- Day 5 — Integration failure modes (retries, idempotency)
- Day 6 — Behavioral: security vs speed conflict
- Day 7 — Mock loop; score on the rubric
Comp context
Directional TC discussions often land around $200K–$420K. Details: Sierra AI FDE salary hub. Peers: Glean, Harvey.
Related hubs
Jump across salary, interview, and role-comparison pages for the same decision path.