# Depth

**Depth** is how much effort to spend on a request. It is the only quality dial, and it never names a
model — internal models can change without breaking your integration.

| Value | Use when | Papers considered | Latency | Cost |
|---|---|---|---|---|
| `standard` | interactive UI, short questions | fewer | fastest | lowest |
| `high_quality` | technical questions needing careful reading | more | moderate | higher |
| `deep_review` | agentic synthesis across the literature | most | minutes | highest |

| Value | `max_papers` ceiling | Latency p50 / p95 | Search credits |
|---|---|---|---|
| `standard` | 20 | 6 s / 15 s | 5 |
| `high_quality` | 50 | 20 s / 45 s | 15 |
| `deep_review` | 200 | 90 s / 240 s | 60 |

`max_papers` above a tier's ceiling is clamped, not rejected. `deep_review` is available on searches
and chat messages, not on topic searches or extractions.

## Choosing

Default to `standard` and escalate on demand — most user questions do not need a deep review, and
depth is the largest single driver of both cost and latency. For `deep_review`, stream the result or
use a webhook; do not block a request thread on it.

## Related

searches · chats · credit · streaming-deep-review