Compare versions on the Traffic tab

The Traffic tab shows each version of an assistant side by side on the calls it actually handled, so you can tell whether a new version is better. Use it to decide whether to raise a canary’s share, keep a test running, or roll back, without exporting call logs or building your own report.

Every number on the tab comes from real calls in the window you choose. It does not change how calls are routed; to change the split itself, use the traffic editor described in Traffic splitting.

What the tab shows

The tab opens on the current split, from the moment it took effect until now. From top to bottom, it shows:

Each version keeps the same color in every view, so you can follow v7 from the flow down to the last table without rereading labels.

Before you start

• Anyone with the Admin, Editor, or Viewer role can open the tab. If your organization uses custom roles, the role needs read access to both calls and traffic allocations, because the metrics are built from call data.
• The tab is most useful once the assistant has more than one published version and some calls. A split with a few dozen calls per version tells you far less than one with a few hundred.

Open the Traffic tab

Choose the time range

The range menu at the top of the tab sets the window every view reads. It offers:

• Since split started: the default. From the moment the current split took effect until now.
• Last 24 hours, Last 7 days, and Last 30 days: fixed windows ending now.
• Previous splits: the five most recent splits before the current one, newest first. Each is named by the dates it ran, such as Split Oct 1 – Oct 6, 2026, with its configured shares underneath, such as v3 90% · v4 10%. Picking one shows that split exactly as it ran, from the moment it took effect until the moment it was replaced.

Last 24 hours, and any previous split that ran for less than two days, are shown per hour. Every other range is shown per day.

Focus on specific versions

The versions menu, next to the range menu, lists every version that handled calls in the window. Clear a version to hide it from every view at once; the menu then reads, for example, 2 of 3 versions. At least one version always stays shown.

You can also focus straight from the flow: select a version’s card to show only that version, and select it again to bring the others back. Hovering a version in the flow highlights its rows in the tables below.

When you hide versions, the flow’s shares are recalculated over the versions still shown, so they keep adding up to 100%.

Read each view

Flow

The flow is a diagram of the window’s calls. On the left is every call the assistant received; in the middle, each version’s card shows how many of those calls it handled and its configured share; on the right, those calls fan out into how they ended. A thick ribbon from a version into an unexpected ended reason is often the first sign a new version behaves differently.

A version that isn’t part of the current split says Not in current split on its card. When the assistant follows the latest published version rather than an explicit split, versions say Follows latest version instead.

Calls per day

This chart shows how many calls each version received in each bucket, with each version’s total in the legend. Use it to confirm calls are actually reaching a new version, and to spot a version that stopped receiving calls. Switch the card to its table view to see exact counts per day, or per hour on short ranges.

Configured and actual share

This view compares each version’s configured share, the percentage of calls the split assigns it, with its actual share, the percentage of calls it received. Small gaps are normal. Repeat callers are kept on the same version where possible, and calls that request a specific version, by setting assistantVersion in the create call request, skip the split, so actual shares drift from configured shares, especially on low volume. A large or growing gap is worth investigating.

When no version shown has a configured share, the configured bar is replaced by a short note explaining why, for example No configured share: every call goes to the newest published version.

Duration, cost, and latency

This table lists one row per version, with these columns:

• Duration: how long calls lasted.
• Cost per minute: the average cost of a minute of call. Expand it to see the parts: LLM, STT, TTS, Vapi, and Transport.
• Turn latency: how long the assistant took to start responding after the caller finished speaking, averaged over each call. Expand it to see the Transcriber, Model, and Voice stages.

Use the p50 and p95 toggle to switch duration and latency between the typical call and the slow tail. Sort any column to rank the versions by it. Each bar shows the value against the largest value in its column, so the slowest or most expensive version is easy to spot.

Why calls ended

This table lists each ended reason, such as Customer ended call or Silence timed out, with the share of each version’s calls that ended that way and the count. Shading makes the larger shares stand out, so you can compare versions without reading every number. If some calls didn’t record a reason, they appear in a No ended reason recorded row, so each version’s column still accounts for all of its calls.

For what each reason means, see Call ended reasons.

Example: decide whether to ramp a canary

Say your scheduling assistant runs on v6, and a week ago you published v7, with a tighter rescheduling prompt, as a 10% canary. To decide what happens next:

Which calls and splits the tab shows

• Metrics follow calls, not the split. A version appears on the tab when it handled calls in the window, even if it’s no longer in the split. A version in the split that handled no calls in the window doesn’t appear.
• Calls with no version aren’t shown on the tab. Calls the assistant handled before it was versioned are left out of the tab’s views. The API still returns them in the unversioned row.
• Old splits stay in history. The range menu reaches the current split and the five before it. Every split, however old, is listed in traffic history, and the API accepts any window.

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