# HarnessScope [Health: Active]

**Category:** 📊 Monitoring  
**Repository:** https://github.com/moongioh/harness-scope  
**GitHub Stars:** 1  
**Views:** 0  
**Installs:** 0  
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**Directory Page:** https://allmcps.com/mcp/harnessscope

## Description
Turn-level governance observability for Claude Code transcripts. Local-first, no LLM inside.

## Claude Desktop Quick Installation
Install path detected from listing signals. Uses `npx` (confidence: high):

```json
"mcpServers": {
  "harnessscope": {
    "command": "npx",
    "args": ["-y","hscope"]
  }
}
```

## Documentation & README

# HarnessScope

<!-- mcp-name: io.github.moongioh/hscope -->

[![PyPI](https://img.shields.io/pypi/v/hscope)](https://pypi.org/project/hscope/)
[![npm](https://img.shields.io/npm/v/hscope)](https://www.npmjs.com/package/hscope)
[![CI](https://github.com/moongioh/harness-scope/actions/workflows/harnesses.yml/badge.svg)](https://github.com/moongioh/harness-scope/actions/workflows/harnesses.yml)
[![License](https://img.shields.io/badge/license-Apache--2.0-blue)](LICENSE)
[![Python](https://img.shields.io/badge/python-3.11%2B-blue)](#)

**Turn-level governance observability for agent harnesses.** HarnessScope reads the transcripts
your agent harness already writes, judges every turn against your workspace's own operating rules
(plan-before-code, verify-before-done, context budget, path boundaries, …), and serves a local
viewer that shows *how* each session traversed that governance structure — passes included, not
just violations.

![HarnessScope — replay, circuit, rule health, token loss](https://raw.githubusercontent.com/moongioh/harness-scope/HEAD/docs/demo.gif)

*Every frame above is `hscope demo`: a synthetic corpus, generated locally. Real transcripts
carry full prompt text and are never demo material.*

---

## What it found

A session is not one model talking to itself — it spawns subagents, they run on models the parent
does not, and a streamed response writes the same request several times. Read that structure
naively and the numbers are wrong. These are the corrections, each measured on this project's own
transcripts:

| Read naively | Actually | Why |
|---|---|---|
| Re-read waste | **42% of it was false** | A subagent reading a file the parent read has not re-read anything — it never had those tokens. Waste is charged per context window (`agent_id`), not per session. |
| 90,957,147 output tokens | **32,348,242** (2.8× overcount) | A streamed response writes several usage records per `requestId`. Count the *last* one — the early ones are partial (2, where the finished response says 31,979). |
| 3,121 turns | **2,438** (28% inflation) | A turn is one user prompt (`promptId`). Interrupt notices, `<command-name>` echoes and `<bash-input>` blocks are user records too. |
| A stable format | **29 harness versions in one month** | The transcript format is undocumented and it moves. So `hscope doctor` fails loudly and names the version that broke it, instead of emitting a wrong number quietly. |
| The re-read waste that survived that | **81% of it was false too** | Keyed on `(context, path)`, *paging* a large file (`offset=501`) is indistinguishable from reading it twice — and each new chunk was charged as tokens the context already held. 692,292 of 854,334 tok. The key now carries the span. |

The last row is the one that matters most, and it is the youngest: it was found **after v0.1.3
shipped**, by pointing the tool at its own workspace and reading the answer. The same class of
mistake as row one, one layer further down, in code that had already passed its own tests. A tool
that claims to catch a governance failure had better survive being aimed at itself — so that is now
the standing use of it, and what it said next was worse.

It cost three rules their default. R1 (index-first), R2 (inline-first) and R6 (approval-gate) ask
**semantic** questions — *is this a domain question? was this fan-out warranted? is this code under
that plan?* — and answered them with **syntactic** tests: a keyword in the prompt, the prompt's
character count, the project folder. Measured against real sessions, 84% of R2's violations were
turns invoking a command whose entire job is to fan out. That is not a threshold in need of tuning;
a proxy that does not track the concept cannot be tuned into one. **They now ship disabled, each
carrying the false-positive rate it was measured at** (`precision`, a first-class field on the rule,
surfaced in the model, in `rule_health`, and as a hoverable badge). Off is not the point — *off, and
here is why, with the number* is the point. A rule silently shipped on is how a governance screen
becomes noise nobody trusts, which is the failure this project exists to name.

R8 stopped reporting a compliance rate for the same reason. Its opportunities *are* its violations by
construction — a re-read counter never observes a *compliant* re-read — so "0% compliance" was an
identity, not a finding: a number that reads like an indictment and says nothing. It reports its
quantity now, and no ratio.

These are observations of **one corpus, not a benchmark** — your numbers will differ. The point is
that they are *readable at all*: metrics know quantities, a bill knows money, and neither knows the
word "subagent". Full reasoning: [`docs/MULTI-AGENT.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/MULTI-AGENT.md).

## How HarnessScope compares

HarnessScope watches a different layer than most "LLM observability" tools: not the app you
instrumented, but the **agent harness itself**, read from its own transcripts.

| Tool | Watches | How it gets data | Runs |
|---|---|---|---|
| **HarnessScope (`hscope`)** | Governance compliance + token flow of Claude Code sessions, turn by turn | Reads transcript JSONL — after the fact, or live as the harness appends it (`--watch`). Zero instrumentation, no hooks into the session | Local, no LLM inside |
| `ccusage` and similar CLIs | Token/cost totals from the same transcripts | Reads transcript JSONL | Local |
| LangSmith / Langfuse | Traces of LLM calls **your application** makes | SDK instrumentation you write | SaaS (Langfuse also self-host) |
| Arize Phoenix (OpenInference) | OTel traces of LLM apps you instrument | OTel SDK instrumentation | Local / self-host |
| Claude Code `/cost`, OTel metrics | The current session's spend; aggregate counters | In-harness | In-harness |

The row nobody else covers: *did the session follow the workspace's operating rules* —
plan-before-code, verify-before-done, path boundaries, context budget. Cost tools tell you
what a session spent; tracing tools tell you what your app's LLM calls did; HarnessScope
tells you whether the agent worked the way your workspace says agents must work.

## Try it — 30 seconds, none of your data

```bash
pipx install hscope        # or: pip install hscope · npx -y hscope  (Python 3.11+ either way)
hscope demo --serve        # synthetic corpus → ingest → judge → viewer
```

Three invented sessions: one compliant, one wasteful (re-reads, dead context, a boundary read, a
completion declared with nothing verifying it), and one fan-out (two subagents — one cites what it
read, one does not; one spawned in the background — plus an off-host MCP round trip).

The corpus is held to the same standard as real data: it must satisfy `hscope doctor`, so a
generator writing a shape the parser does not expect gets caught by the invariants. It already
earned that twice — a `requestId` reused across sessions (which hscope correctly read as one API
call replayed by a fork), and a padded `agentId:` that the parser's regex swallowed whole.

## Then point it at your own sessions

```bash
hscope                     # scan ~/.claude/projects → ingest → judge → check → open the viewer
```

No flags, no config file. Two things it will not get wrong:

- **The port is found, not assumed.** 8000 is a reasonable default and on some Windows machines it
  is a reserved range (WinError 10013). A first impression should not be a stack trace.
- **It says that transcripts expire.** The harness deletes them after about 30 days, and **ingest
  is what makes them permanent**. Ingest less often than that and you lose sessions silently — a
  session never ingested is indistinguishable from one that never happened. The first run prints
  how old your oldest transcript is and prescribes a cadence.

It also announces which rules it is about to judge with — neutral presets, or the workspace model
it found on disk. Claiming "presets" while quietly applying a model would be the same lie as a
silent fallback.

Everything is **local-first**: no transcript data leaves your machine (the one exception — the
opt-in Tier B LLM judge — is off by default and fires only on an explicit per-session click). The
tool never writes to your projects, your `.mcp.json` or your harness settings: *a tool that observes
governance must not reshape the surface it observes.*

## Watch it live — and *only* watch

```bash
hscope --watch             # the circuit stays live: sessions are re-ingested and re-judged as they run
```

The harness appends to the transcript while the session is still going, so the data for a live view
was always there — what was missing was the loop. `--watch` scans mtimes every 2s, hashes only the
files that moved (mtime is the trigger; the hash is still the decision), re-judges only those
sessions, and the viewer refreshes itself. A tick where nothing moved parses nothing, hashes nothing
and prints nothing.

**It observes; it does not intervene.** No hook is installed in your session, nothing is blocked,
and a violation on screen is one *a human* has to act on. Blocking would mean a `PreToolUse` hook —
which would make the "no hooks into the session" row above false, bind the tool to one harness, and
let a wrong verdict stop your work (post-hoc, a bad call is a bad badge; live, it is a stopped
hand). Seeing a re-read loop or a fan-out at 5k tokens instead of 40k is worth having; it does not
require the tool to hold the brake.

**The turn that is still running is shown, not judged.** Judging it would break hscope's own rules:
a verification-gate rule would fire on the very turn that is *about* to run the check — a verdict
overturned three seconds later — and a streamed response's token usage is not final until its last
record lands. So the live turn wears an *in flight · not judged* badge and its verdict appears when
the turn ends. A verdict deferred must not become a verdict skipped: if you interrupt that turn the
file simply goes quiet, and hscope judges it once its liveness window lapses rather than leaving it
withheld forever.

## What you get

### Harness Circuit
![Harness Circuit](https://raw.githubusercontent.com/moongioh/harness-scope/HEAD/docs/img/circuit.png)

One turn as a fixed-topology schematic: context sources → agent → action surfaces → governance
outputs. Subagents are nodes with a spawn edge *and* a return edge — labelled with what came
**back**, which is not what the subagent **spent** (one real turn: three agents burned 16.5k / 6.3k
/ 5.3k output tokens and handed the parent 1.5k / 2.2k / 2.0k). Off-host MCP hops and write-capable
servers are flagged on the wire.

### Session Replay
![Session Replay](https://raw.githubusercontent.com/moongioh/harness-scope/HEAD/docs/img/replay.png)

The turn timeline: what was loaded into context, which tools ran, and the rule verdict on each turn
— passes included. A governance view that only lists violations cannot tell "compliant" from
"never checked".

### Rule Health
![Rule Health](https://raw.githubusercontent.com/moongioh/harness-scope/HEAD/docs/img/health.png)

Compliance × coverage, per rule. A rule at 100% compliance over 3 evaluable turns is not the same
as one at 100% over 300, and a rule nothing can evaluate is reported as such rather than scored.

### Token / Loop
![Token and loss](https://raw.githubusercontent.com/moongioh/harness-scope/HEAD/docs/img/loop.png)

Per-turn token burn with loss pinpoint markers — re-reads, dead context (loaded, never cited),
error churn, cache-window waste — attributed to the turn and the context window that actually paid.

### Setup

Every hook, MCP server, skill and subagent you registered, next to what your transcripts show was
actually called: `active` / `unused` / `unregistered-call`. Registration is a claim; the transcript
is the evidence. (No screenshot here on purpose — this screen reads *your* machine's configuration,
so any capture of it would be a picture of someone's real workspace.)

## Rules you did not have to write

Nobody should hand-write rules to try a tool. When the first run finds no workspace model, it seeds
one from your repo's structure and leaves a page for the LLM you already have:

```bash
hscope                   # ...with no rules of your own, writes ~/.hscope/<id>/HSCOPE-SETUP.md
hscope mcp --install     # prints an MCP snippet; paste it into .mcp.json
hscope setup             # regenerate the page whenever your canon moves
```

`HSCOPE-SETUP.md` has two readers. For you: the canon, hooks, MCP servers, skills and subagents
hscope found, and the canon clauses no rule cites yet. For your LLM: instructions to call
`get_setup_guide` → `suggest_rules` → `set_rule` and write those rules. **You approve; it drafts.**

The whole journey is **three manual actions** — run `hscope`, paste the snippet, hand over the page.
The snippet carries `HSCOPE_MCP_WRITE=1`, so pasting it *is* the write consent; there is no second
step. And hscope never edits `.mcp.json` itself.

## Did the onboarding actually work?

```bash
hscope onboard      # read-only, idempotent; exit 1 while incomplete
```

Six observed stages and a verdict. `hscope` prints it at the end of every run, so you meet it
without knowing the command exists.

```
1  transcripts ingested             PASS   297 session(s), oldest 35d
       -> oldest is 35d and the harness deletes transcripts at ~30d -- ingest more often
2  hscope MCP registered            FAIL   not in your harness config
       -> run `hscope mcp --install` and paste the snippet it prints
3  workspace model exists           PASS   ~/.hscope/warp/workspace-model.json
4  the model governs your sessions  PASS   289 of 297 session(s)
5  the model is not empty           PASS   14 rule(s), 25 role(s)
6  your rules actually fire         PASS   10 of 10 enabled rule(s) had an opportunity

disabled, so not judged at all: R1, R2, R6, B1

INCOMPLETE -- next: step 2, hscope MCP registered
```

Four of those are a checklist. **Two of them fail silently, and they are why the command exists:**

- **Step 4 — the model governs *your* sessions.** A model can sit on disk while its
  `workspace.roots` claim none of the paths you actually work in. hscope then judges with the
  neutral presets, and until this gate it said nothing about it — so you would read your own rule
  names on a screen that never applied one. It now prints the cwds your sessions really ran in.
- **Step 6 — your rules actually fire.** Twelve rules an LLM wrote for you that never get an
  opportunity on your corpus are not an onboarding; they are a green check over nothing. Rules with
  zero opportunities are **named**. A rule that is merely *disabled* is reported as off, not dead —
  those are different facts and conflating them is the kind of lie this tool exists to catch.

A dead rule is a finding, not a failure: coverage of zero can honestly mean "no chance yet", and
failing the gate on it would reward writing fewer rules. But if *nothing* you wrote ever fired,
the gate says INCOMPLETE — that is a vacuous pass, and `hscope doctor` already refuses to report one
of those about your transcripts. This is the same refusal, pointed at your setup.

## The workspace model (optional but recommended)

Without a model, HarnessScope runs on **neutral presets**: generic rules with empty domain values,
path labels fall back to file names, sessions render as a flat list. Crash-free in any repo — that's
the de-domaining contract.

With a model (`~/.hscope/<workspace>/workspace-model.json`) you declare, in one JSON document, how
*your* workspace is governed:

- `rules[]` — archetype instances with your params (keywords, thresholds, markers)
- `roles[]` — what each path / MCP server / subagent *means* (label, circuit node, host boundary)
- `gates[]` — your governance pipeline (e.g. context-load → plan-approval → implement → verify → ledger)
- `unmeasurable[]` — canon clauses no detector can check (surfaced honestly instead of faked)
- `work_items` — optional grouping above sessions (this workspace: `plans/**` with a status
  frontmatter; other repos can map issues/PRs into the same slot). Absent ⇒ flat sessions.

Schema and a neutral example live in `hscope/schema/`. Validate yours:

```bash
python -m hscope.schema.validate_model ~/.hscope/<workspace>/workspace-model.json
```

## MCP surface

Any MCP client can read what HarnessScope observed — and the loop closes: an agent opens a session
by reading how the last one scored, instead of re-earning the finding.

```jsonc
// .mcp.json
{ "mcpServers": { "harness-scope": {
    "command": "python", "args": ["-m", "hscope.cli", "mcp", "--db", "/path/to/harness_scope.db"] } } }
```

| Tool | |
|---|---|
| `list_sessions` · `session_report` · `token_hotspots` · `rule_health` | the viewer's numbers |
| `get_workspace_model` | how this repo is governed, as one document |
| `get_setup_guide` · `suggest_roles` · `suggest_rules` | evidence for authoring rules |
| `set_role` · `set_rule` | write them back |

**No model runs inside this server.** The client *is* the model: `get_setup_guide` hands it the
closed archetype library and each archetype's param schema, `suggest_rules` hands it the canon
clauses no rule cites, and the judgment comes back through `set_rule` — where the params are
validated against that archetype's schema before anything is written. So the MCP path needs no
provider, no credential and no off-host consent. `hscope compile` does the same job in one batch
LLM call; this is its conversational, incremental counterpart.

Writes are **off by default** (`HSCOPE_MCP_WRITE=1`) and can only ever touch
`~/.hscope/<workspace>/workspace-model.json`. There is no tool that writes a project file or steers
another agent — HarnessScope observes and judges; it does not drive.

## Docs

| | |
|---|---|
| [`MULTI-AGENT.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/MULTI-AGENT.md) | Why a session is not one model talking to itself — and every number in *What it found* |
| [`DOCTOR.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/DOCTOR.md) | `hscope doctor`: nine invariants, and the two things it refuses to do |
| [`FAILURE-MODES.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/FAILURE-MODES.md) | Graceful degradation — what happens when a transcript, DB or model is wrong |
| [`VERIFICATION.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/VERIFICATION.md) | The verification harnesses (Definition of Done); CI runs them on 3 OSes |
| [`CONFIG.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/CONFIG.md) | Environment variables · the opt-in Tier B judge |
| [`RUN-FROM-SOURCE.md`](https://github.com/moongioh/harness-scope/blob/HEAD/docs/RUN-FROM-SOURCE.md) | Contributors: requirements, the pipeline stage by stage, repo layout |

## FAQ

**What is HarnessScope?**
A local-first observability tool for Claude Code: it parses your transcript JSONL files into
SQLite, judges every turn against your workspace's own operating rules, and serves a web viewer
showing how each session traversed that governance structure. Install with `pip install hscope`
(or `npx -y hscope`).

**Does my transcript data leave my machine?**
No. Parsing, rule evaluation and the viewer are all local; the server binds `127.0.0.1`. The one
exception is the opt-in Tier B LLM judge, which is off by default and sends a single per-session
digest only when you click that session's judge button.

**Do I need an API key or an LLM to run it?**
No. There is no model inside HarnessScope — the rule engine is deterministic. An LLM only enters
the picture where you bring your own: the optional Tier B judge, or your coding agent authoring
rules over the MCP surface.

**How is this different from ccusage, LangSmith, or Phoenix?**
Different layer (see the comparison table above). Cost CLIs total what a session spent; tracing
platforms instrument *your application's* LLM calls. HarnessScope reads the *harness's* own
transcripts and judges governance: whether sessions planned before coding, verified before
claiming done, stayed inside path boundaries, and where their tokens actually died.

**Can my agent read the results?**
Yes — that is the point of the MCP surface. Any MCP client gets `session_report`,
`token_hotspots`, `rule_health` and the workspace model, so the next session opens by reading
how the last one scored instead of re-earning the finding.

**What happens when Claude Code changes its transcript format?**
`hscope doctor` fails loudly, naming the harness version that broke an invariant, instead of
quietly emitting a wrong number. This corpus alone declares 29 harness versions in one month;
drift is detected, not tuned away.

**Which platforms does it run on?**
Windows, macOS and Linux — the CI matrix runs the verification harnesses on all three.
Python 3.10+ (3.11+ recommended).

## Data & privacy

- The SQLite DB contains **full prompt text** from your transcripts. It is gitignored (`*.db`) and
  must stay local — never commit or upload it.
- The server binds `127.0.0.1` by default and is read-only over the DB.
- Tier B (LLM judge) sends a per-session digest off-host **only** when you click the judge button
  for that session; the rule (`B1`) ships disabled.

## License & open-core boundary

HarnessScope is **Apache-2.0 open core**. Everything an individual user touches is free forever,
with no feature limits — paid tiers (if/when they exist) only ever add things an *organization*
needs, never remove things from individuals:

| Layer | Free (Apache-2.0 core) | Enterprise (`ee/`, future) |
|---|---|---|
| Capture | Transcript ingestion + hooks | MCP gateway (cross-harness capture) |
| Analysis | Rule engine · circuit · token loss · coverage — all of it | Multi-user aggregation, org dashboards |
| Security | Local security-flow rules (self-audit) | Org compliance reports, audit logs |
| Accounts | Local, single user | SSO / RBAC |

See [`LICENSE`](https://github.com/moongioh/harness-scope/blob/HEAD/LICENSE) (Apache-2.0), [`ee/README.md`](https://github.com/moongioh/harness-scope/blob/HEAD/ee/README.md) (boundary), and
[`CONTRIBUTING.md`](https://github.com/moongioh/harness-scope/blob/HEAD/CONTRIBUTING.md) (DCO).

