Harness coverage

Not every AI coding tool speaks OpenTelemetry. Trove captures the ones that do by flipping their flags, and captures the ones that don’t by deriving telemetry from what they leave on disk. Understanding which path a harness takes tells you what data to expect from it. This is the concept behind the coverage badges on the Harnesses tab.

Native OTel

Some harnesses emit OTLP themselves. For these, Trove’s job is small: write a managed region into the tool’s config that turns on its OTLP export and points it at the local collector. The tool does the rest.

Native-OTel harnesses: Claude Code, Antigravity CLI, Codex (CLI and desktop), Qwen Code, OpenCode, and Cursor IDE. Claude Desktop is auto-detected via a local audit log with no setup.

Because the signal originates in the tool’s own instrumentation, native coverage is the highest fidelity Trove offers:

• Events — accurate, from the tool’s own event stream.
• Tokens — exact, from the tool’s own counts.
• Cost — exact, computed from real token usage.
• Durations and errors — reported by the tool.

Best effort (watchers + wrappers)

Other tools never emit OTel. Trove can’t make them — but it can watch what they do and translate it into equivalent OTLP records. Two mechanisms:

• Watchers — filesystem monitors that tail a tool’s on-disk records. Cline’s watcher, for example, tails its ui_messages.json task records and classifies each new entry by type into Tier A events.
• Shell-rc wrappers — a managed block in your shell rc file defines a wrapper function around the tool’s command. The wrapper re-execs the real binary, records each invocation (timestamp, duration, exit code), and emits OTLP from that. Aider and GitHub Copilot CLI work this way.

Best-effort harnesses: Cline, Aider, and GitHub Copilot CLI.

The derived records share the same Tier A queries as their native peers — a chat.turn from Aider sits in the same trove.harness.events series as a chat.turn from Claude Code. The difference is fidelity:

• Events — reliable (one per invocation, or one per classified record).
• Durations — reliable (the wrapper times the real process).
• Tokens — estimated. Trove only sees prompt/response byte length, not the upstream tokenizer’s count, so it approximates (bytes / 4).
• Cost — estimated, from those approximate tokens × the rate table.
• Errors — derived from non-zero exit codes.

Caution

Best-effort cost and token figures are directional, not invoice-grade. They carry cost.method = "estimated" so you can filter them out when you need exact numbers — see Tier A metrics.

Partial coverage

A middle case: the tool exposes some of its events but not all. Cursor CLI is the example — it surfaces only a subset of Cursor’s hook events (shell-exec), so Trove captures that subset and nothing more. Partial harnesses get a distinct badge so you know the data is genuine but incomplete.

At a glance

Coverage	How Trove captures it	Events	Tokens	Cost	Examples
Native OTel	Flip the tool’s OTLP flags	Accurate	Exact	exact	Claude Code, Antigravity CLI, Codex, Qwen, OpenCode, Cursor IDE
Partial	Capture an observable subset of events	Subset only	—	—	Cursor CLI
Best effort	Watchers + shell-rc wrappers derive OTLP	Reliable	Estimated	estimated	Cline, Aider, Copilot CLI

Note

A fourth class — setup guide harnesses (Junie CLI, Droid, Kimi Code CLI, Devin, ForgeCode) — can’t be auto-patched yet, so Trove links to manual setup instructions instead of a one-click toggle. Each adapter declares which Tier A metrics it can emit, so sparse rows across harnesses are expected and normal.

Reversibility is the same for both

Whether Trove flips a native flag or installs a wrapper, the change is made through a sentinel-bracketed managed region and reverts byte-for-byte on Disable — config files, shell rc, and all. No coverage tier leaves residue behind.

Where to go next

Harnesses Enable harnesses and see their coverage badges.

Tier A metrics The schema both native and derived records feed.

Mappings Synthesis rules for native tools, hook rules for watchers.

The collector The localhost sidecar every harness routes through.