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Documentation Index

Fetch the complete documentation index at: https://docs.tell.rs/llms.txt

Use this file to discover all available pages before exploring further.

Stream events, logs, and syslog messages as they flow through Tell’s pipeline. The tail connects to a running Tell server via Unix socket and decodes batches in real time — useful for debugging, monitoring deploys, and verifying that data is flowing correctly. 
tell tail
This streams everything. In production, you’ll want filters.

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Filtering

Server-side filters are applied before data leaves the server — use these to reduce volume: 
# Only events from workspace 1
tell tail --workspace 1

# Only error logs from the HTTP source
tell tail --type log --level error --source http

# 1% sample at max 100 batches/sec
tell tail --sample 0.01 --rate-limit 100
Client-side filters match content after decoding: 
# Events matching a glob pattern
tell tail --event "purchase_*"

# Regex match across any string field
tell tail --match "timeout|connection refused"

# Combine: error logs mentioning payments
tell tail --type log --level error --match "payment"
All filter flags are repeatable — --workspace 1 --workspace 2 streams from both.

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Output formats

tell tail                          # colored text (default)
tell tail --output json            # one JSON object per event
tell tail --output compact         # single-line summary per event
tell tail --output raw             # raw decoded FlatBuffer data
tell tail --metadata-only          # batch metadata without payload decode
Use --output json for piping into jq or other tools: 
tell tail --type event --output json | jq '.event_name'

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Replay

Replay the last N batches from the server’s ring buffer on connect: 
tell tail --last 50
This is useful for catching up on what just happened without waiting for new data.

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Setup

The tail connects to Tell’s tap server via Unix socket. The tap server starts automatically with tell run — no extra configuration needed. The default socket path is derived from your data directory. To connect to a specific socket: 
tell tail --socket /tmp/tell-tap.sock
tell tail is available on Unix systems only (macOS, Linux). It requires the tail feature flag at build time, which is included in the default build.

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