---
name: library-manager
description: >-
  Manage Vecmocon's component library. Extract parameters from a component datasheet PDF into the
  per-typeid Excel template. Checks Gitea for a duplicate MPN_make, classifies to a typeid, updates that typeid's template (versioning, changelog, backfill), fills
  a per-part workbook with human verification, reads the Altium symbol/footprint refs, assembles
  a part folder and pushes to Gitea. Can UPDATE an existing part instead of hard-stopping, and can
  WRITE the mandatory SOP parameters directly into a .SchLib symbol while stripping Ultra-Librarian
  defaults. On the .SchLib task it also fills that component's Excel (Description + all parameters)
  and pushes the updated symbol to Gitea, no verification loop. Descriptions
  follow Vecmocon's strict Altium Description Format. Use whenever the user uploads a datasheet,
  builds/updates a library entry, adds a template parameter, fills/updates .SchLib parameters, or
  pushes a part to Gitea. Always trigger on "\datasheet", "\library", "\library-manager", "\schlib".
---

# Library Manager

Turn one component datasheet into a verified, versioned library entry in Gitea. The guiding
idea is honesty and traceability: every value lands in the right column and unit, anything
the datasheet doesn't state stays blank, and nothing reaches Gitea until a human has
confirmed it.

## Ask, don't assume

This is a deliberately **interactive** skill. At every decision point, **ask the user and
wait for an answer — do not assume a default and proceed.** In particular, always confirm:
the **make**; the **typeid/classification** you inferred; whether any **new parameters**
should be added to the template; the extracted **values** (the verification loop); that the
**symbol/footprint actually match this part**; and whether to **apply a new parameter to
existing parts** (backfill). When something is ambiguous, ask a specific question rather than
guessing. It is always better to ask one more question than to write the wrong thing into the
library.

One more thing to confirm when a part **already exists**: whether to **update it or stop**
(don't silently overwrite), and if updating, **which fields change** (values, symbol/footprint,
datasheet). An update still goes through the same verification loop before anything is pushed.

**Pushing is the exception — push automatically.** Once a part is verified and assembled (or a
template/version change has been made, or a verified update is ready), push to Gitea **on your
own, without asking for confirmation**. Never add a "shall I push?" step — just push, then tell
the user where it landed. (You still flag a genuine symbol/footprint mismatch, because that's a
correctness issue, not a push confirmation.)

**Symbol parameters are a second exception — stamp them without asking, every time.** This
holds in both directions. As a standalone task (the engineer hands over a `.SchLib`): fill that
component's Excel (Description + all parameters) and push the updated symbol automatically,
without pausing to confirm the values. And **inside the normal new-part flow**: once the symbol
is uploaded at step 6, stamp the SOP + sheet parameters onto it and strip the Ultra-Librarian
defaults as a matter of course — do **not** offer it as a follow-up, do **not** ask whether the
engineer wants it, and never push a part folder whose symbol still carries UL defaults. See
*Mandatory symbol parameters* for why this path skips the loop. Every other flow keeps the
normal interactive asks below.

## Inputs

- **A datasheet PDF whose filename is the MPN** (e.g. `BAT46WJ.pdf`). If it's a series
  datasheet, search that exact MPN inside to read the correct variant.
- **The make** (manufacturer), given by the user. The `make` tag is the first word of the
  manufacturer, alphanumerics only (Texas Instruments → `Texas`, Nexperia → `Nexperia`).
- **Later in the flow**, after verification: an Altium **symbol** (`.SchLib`) and
  **footprint** (`.PcbLib`) file, provided by the user.

## The identifier: `MPN_make_typeid`

Every part folder, every per-part workbook, and column A of every sheet (`MPN_make_type`)
use the same tag:

```
<MPN>_<make>_<typeid>        e.g.  BAT46WJ_Nexperia_SCH
```

`typeid` is the part's type-ID code from the taxonomy (`references/taxonomy.md`, full source
`assets/template/Type_ID.xlsx`) — Schottky → `SCH`, MOSFET → `MOS`, LDO → `LDO`. In the new
template **each typeid is its own sheet** (125 of them). The broader **Class** (Diode,
Transistor, IC …) is used only to organise the library repo into top-level folders.

## Gitea layout (two repos)

```
skill repo/            this skill's own files (updated versions land here too)

library repo/
  <Class>/                         e.g. Diode, IC, Transistor, Resistor, ...
    <MPN>_<make>_<typeid>/          e.g. BAT46WJ_Nexperia_SCH
        <MPN>_<make>_<typeid>.xlsx  this part's own one-row parameter sheet
        <MPN>_data.pdf              the datasheet
        <symbol>.SchLib             user-provided
        <footprint>.PcbLib          user-provided
```

There is **no single master workbook** — each part carries its own sheet inside its folder.
Connection + repo names live in `config/gitea.env` (`SKILL_REPO`, `LIBRARY_REPO`), so runs
need no per-session token. If the host is unreachable, the git steps fail clearly and write
nothing.

## Who's running this (operator identity)

The whole org shares one Claude account and one Gitea token, so the skill can't tell who's
running it on its own. Instead it records the **operator's name** on everything it pushes, and
asks **only once per person**. Establish the identity at the very start of a run:

1. Read `~/.library-manager-id` on the operator's machine (via the desktop bridge):
   `cat ~/.library-manager-id`.
2. **If it exists** (JSON like `{"name":"Priya Sharma","email":"priya@vecmocon.com"}`) → use it,
   **don't ask**.
3. **If it does NOT exist → this person isn't onboarded yet, so ask once** (do this even though
   the config carries a default, so a teammate is never silently logged as "admin"):
   > "First time using the library skill on this machine — what name should your library
   > changes be recorded under? (If you're the admin, just enter `admin`.) And your email,
   > if you have one."

   Then save it so it's remembered forever:
   `echo '{"name":"<Name>","email":"<email>"}' > ~/.library-manager-id`. Every later run finds
   it in step 1 and never asks again — the admin answers `admin` once, each teammate answers
   their own name once, and from then on everyone is attributed correctly with no prompt.
4. **Only if you genuinely can't ask** (an unattended / scheduled run, or the machine isn't
   reachable) fall back to the config `OPERATOR` default so the run isn't blocked — and say in
   your summary that attribution used the default rather than a confirmed person.

Then carry that identity through the run:

- pass `--author "<Name> <<email>>"` to every `push-part` / `push-skill` / `commit-push`, and
- pass `--by "<Name>"` to `append_parameter`.

(Equivalent alternatives the scripts also read: `export LM_AUTHOR_NAME=... LM_AUTHOR_EMAIL=...`
for the session, or drop the same `~/.library-manager-id` file in the container home.)

**Identity precedence** (first one that's set wins): `--author` flag → `LM_AUTHOR_*` env →
per-person `~/.library-manager-id` → the per-install **`OPERATOR`** default in
`config/gitea.env`. So this admin install has `OPERATOR=admin`, meaning **every run/push here
is recorded as "admin" automatically**, with no file or prompt needed. A member's own
`~/.library-manager-id` (or an explicit `--author`) overrides that default with their real name.

This stamps the operator onto three things: the **commit author** (shown in `git log`, the
Gitea commit page, and `git blame`), the **commit message** (it ends with `(by <Name>)`, so the
name shows right in Gitea's activity feed), and a **By** column in the changelog. Honest limit:
the top-line "*X* pushed to main" in Gitea's activity still shows the **shared token owner** —
only giving each person their own Gitea token changes that bottom layer.

## Workflow

Run these in order. Each `python`/`bash` command is a helper in `scripts/`.

### 0. Sync the skill state from Gitea first — always

The skill's state (the template, the per-typeid versions, and the changelog) lives in the
**skill repo**, and it grows over time. A fresh install/session starts from the packaged v1
state, so if you don't sync first, a second template change wouldn't build on the first — the
versions would restart at v1 and the changelog would look like it only holds the latest change.
**So begin every run by pulling the current state:**

```bash
python scripts/gitea_components.py pull-skill
```

This copies `template.xlsx`, `versions.json`, and `CHANGELOG.xlsx` from the skill repo into the
local skill, so version bumps continue correctly (v2 → v3 → …) and the changelog stays
**cumulative from the very first change**.

### 1. Duplicate check first — before any real work

The part's presence is keyed on **MPN + make** (typeid not known yet). If it already exists,
stop; re-doing an existing part would only risk overwriting good data.

```bash
python scripts/gitea_components.py check-mpn --mpn <MPN> --make <make>
```

`ABSENT` (exit 0) → this is a **new part**; continue to step 2.

`EXISTS …` (exit 3) → the part is already in Gitea. Don't silently overwrite it, but don't
dead-end either — **ask the user whether they want to update the existing part or stop.** If
they want to revise it (new/corrected values, a swapped symbol/footprint, a newer datasheet),
go to *Updating an existing part*. If not, stop here. (If the user's request already said
"update"/"revise"/"fix" this part, take that as the answer and go straight to the update flow.)

### 2. Classify → typeid (and its Class)

Read the datasheet, identify the part, and match it to the closest subclass in
`references/taxonomy.md`; record its **typeid** (= the template sheet name). The **Class**
(for the library-repo folder) comes from the same taxonomy row —
`scripts/common.py:class_folder(typeid)` returns it (e.g. `SCH` → `Diode`).

### 3. Confirm the typeid's template (and add parameters if asked)

Check whether that typeid has a sheet in `assets/template/template.xlsx`.

- **No sheet for this typeid** → ask the user to upload the template sheet for it. Add it to
  `assets/template/template.xlsx`, then push the updated skill files to the skill repo (see
  *Pushing the skill repo*). Then continue.
- **Sheet exists** → print **all** of that sheet's parameters (its column headers) in the
  chat and ask the user whether any new parameters should be added.
  - **No** → go to step 4.
  - **Yes** → collect the new parameter name(s), then:

    ```bash
    python scripts/append_parameter.py --typeid <typeid> \
        --param "New Parameter(unit)" [--param "Another(unit)"] \
        --desc "why these were added" --by "<operator name>"
    ```

    This appends the column(s) at the end of that typeid's sheet, **bumps that typeid's
    Template Version and Skill Version together** (v1→v2 — see *Per-typeid versioning*),
    and writes one row to the global changelog `assets/CHANGELOG.xlsx`. Then sync the updated
    skill files + changelog to the skill repo with `push-skill` **automatically** (see
    *Pushing the skill repo*) — that merges the new changelog row onto the one already in Gitea
    rather than overwriting it.

    Then ask: **should this change apply to the parts of this typeid already in Gitea?**
    - **No** → go to step 4 (only the current part gets the new column).
    - **Yes → backfill** (see *Backfilling existing parts*), then tell the user the previous
      sheets were updated, and go to step 4.

### 4. Extract and fill the per-part workbook

Read every parameter the datasheet actually states into that typeid's columns, converting to
each header's unit. **Leave blanks where the datasheet is silent — an honest blank beats a
guess.**

The **`Description`** column is special: it is **not** free prose but a strict `_`-joined
engineering string — a type prefix, the defining parameters in a fixed order, package near the
end, optional AEC-Q last (e.g. `CHIP_RES_36kΩ_62.2mW_±0.1%_0402`, `CHIP_CAP_2.2uF_100v_±10%_1210_x7r`,
`SCH_100V_0.25A_SOD-323F`). `references/description_format.md` defines the format for **every**
type in the library: the four the Altium SOP spells out (Resistor, Capacitor, Zener, TVS) are
**strict**; the rest are the house extension on the same basis. Look up the part's type there,
build the Description to that format, and if a real datasheet doesn't fit the format cleanly,
follow the pattern and **flag the mismatch to the engineer** rather than bending it silently.
Collect the values into a small `part.json`:

```json
{"mpn":"BAT46WJ","manufacturer":"Nexperia","typeid":"SCH",
 "values":{"Description":"SCH_100V_0.25A_SOD-323F","Forward Voltage(V)":"0.71",
           "Reverse Voltage(V)":"100","Forward Current(A)":"0.25","Package":"SOD-323F"}}
```

(typeid `SCH` → prefix `SCH`, format `SCH_Vr_Io_Package`, so a 100 V / 250 mA Schottky in
SOD-323F becomes `SCH_100V_0.25A_SOD-323F`.)

```bash
python scripts/fill_templates.py part.json \
    --template assets/template/template.xlsx --dest <stage>/<tag>/
```

This writes `<tag>.xlsx` with column A = the tag, **Skill Version (col B)** and **Template
Version (col C)** stamped from this typeid's current versions, and the four design columns
left blank for now.

The part workbook has up to **two sheets**:

- **Sheet 1** — the typeid's parameter sheet (the one filled row).
- **Sheet 2 — `Version History`** — added **only when this typeid has had a template/skill
  update**. It lists the **cumulative** change history for that typeid (Date, Skill Version,
  Template Version as `v1 → v2`, Description) — every change up to the version this file was
  built at. So a part built at v3 shows both `v1 → v2` and `v2 → v3`; a still-at-v1 typeid has
  no second sheet. The history is read from `assets/CHANGELOG.xlsx`, so make sure the local
  changelog is current (it's kept in sync by `push-skill`) before building parts.

### 5. Human verification loop

Deliver the filled workbook to the user and ask them to verify it. If they report an error
or say it isn't right, **go back to step 4, re-read the datasheet more carefully, re-fill,
and hand it back.** Repeat until the user confirms it's verified. Nothing is pushed until
this passes — the engineer is the ground truth for the numbers. (The standalone `.SchLib` task
is the exception: it fills the Excel and pushes without this loop — see *Fill the component's
Excel and push* under *Mandatory symbol parameters*.)

### 6. Symbol + footprint → the design columns

Once verified, ask the user to upload the **symbol (`.SchLib`)** and **footprint
(`.PcbLib`)** files. Copy them into the staging part folder **under their proper names** (so
the Path columns match the files that actually get stored — strip any upload-staging prefix
the environment may have added), then read all four design values in one shot:

```bash
cp <uploaded_symbol>    <stage>/<tag>/<symbol_name>.SchLib
cp <uploaded_footprint> <stage>/<tag>/<footprint_name>.PcbLib
python scripts/altium_refs.py design \
    --symbol <stage>/<tag>/<symbol_name>.SchLib \
    --footprint <stage>/<tag>/<footprint_name>.PcbLib > design.json
```

This produces (verified against real Ultra-Librarian exports):

- **Library Ref** = the component name **inside** the `.SchLib` (e.g. `CGA3E3X7R1H474K080AE`)
- **Library Path** = the `.SchLib` file name
- **Footprint Ref** = the **base** pattern inside the `.PcbLib`; Altium ships IPC density
  variants (`-L` / `-M` / `-N`) alongside the base, and the base is the one used (e.g.
  `CAP_CGA3_TDK`, not `CAP_CGA3_TDK-L`)
- **Footprint Path** = the `.PcbLib` file name

These Ref names come from *inside* the files and can differ from the MPN or filename. If a Ref
comes back `null` (or a footprint shows several unrelated candidates), ask the user to confirm
the name from Altium's properties and edit `design.json`. Then re-fill so the columns land:

```bash
python scripts/fill_templates.py part.json \
    --template assets/template/template.xlsx --dest <stage>/<tag>/ --design design.json
```

Once you have the symbol and its Library Ref, **stamp the mandatory symbol parameters onto the
`.SchLib` — always, automatically, without asking.** This is not an optional extra and it is not
something to offer the engineer: a symbol that reaches Gitea carrying Ultra-Librarian defaults
instead of the SOP set is an incomplete part. Do it in this same run, before step 7, so the
folder is pushed complete the first time.

Build the parameter set from the datasheet values you already read for the workbook (they are the
same values — Manufacturer, Manufacturer Part, Value, Tolerance, Operating Temperature, RoHS,
Datasheet, Process, Vecmocon Part Code, …), **plus every engineering parameter from this typeid's
sheet** and `Component Type` = the part's Class, then write them in and strip the UL defaults —
see *Mandatory symbol parameters* below for the full set and the exact commands. Skip only the
housekeeping columns (`MPN_make_type`, Skill/Template Version) and the four Library/Footprint
Ref/Path columns — those are Altium's own model links, so duplicating them as parameters would
create two sources of truth.

Don't stop to confirm the values here either; the engineer validates the symbol by opening it in
Altium, which is the real check. Leave genuinely-unknown fields blank (the SOP hides blank
parameters) and **note the gaps in your summary** rather than blocking on a question — the one
field that is never on a datasheet is `Vecmocon Part Code`, so use it if the engineer supplied it
and otherwise leave it blank and say so.

### 7. Assemble the part folder

The staging folder `<tag>/` should now hold the four files: the per-part `<tag>.xlsx`, the
datasheet (name it `<MPN>_data.<ext>`), the symbol (the **stamped** one from step 6, not the raw
upload), and the footprint. If the engineer's upload carried extra files (a `.step` 3D model, a
`.LibPkg`), ask whether to include them — the standard folder is these four.

### 8. Push to the library repo, under the part's Class

```bash
python scripts/gitea_components.py push-part --folder <stage>/<tag> --typeid <typeid> \
    --author "<operator name> <<operator email>>"
```

This places the folder at `components/<Class>/<tag>/` — creating the Class folder if it
doesn't exist yet, or pushing into it if it does — and commits and pushes. Confirm to the
user where it landed.

## Mandatory symbol parameters (.SchLib)

The SOP (§5) requires every schematic symbol to carry a fixed parameter set in its Altium
properties — `Component Type`, `Manufacturer`, `Manufacturer Part`, `Value`, `Tolerance`,
`Operating Temperature`, `ROHS`, `Datasheet`, `Process`, `Vecmocon Part Code`, and the two
second-source fields — with the **Comment** set to the MPN. The skill can stamp these onto the
symbol from the datasheet.

This runs **as its own task too**, not only inside new-part creation: whenever the user hands
over one or more `.SchLib` files and wants their parameters filled/updated (e.g. "\schlib", "add
these parameters to this symbol", "update the schlib"), read the datasheet/specs for each part,
build its `params.json`, and run `scripts/schlib_write.py` per file — same steps as below.

The skill writes these **directly into the `.SchLib` in pure Python** with
`scripts/schlib_write.py` (it rebuilds the OLE around the enlarged `Data` stream, preserving
every other byte, and strips the Ultra-Librarian defaults that shouldn't ship: `Manufacturer_Name`
/ `Manufacturer_Part_Number` (they duplicate the SOP fields), the UL `Copyright` notice, and the
UL `Component_Type` — replaced by Vecmocon's own spaced `Component Type`). Kinds of value:

- **Derived** — `Component Type` = the part's **Class** (`Resistor`, `Capacitor`, `Diode`,
  `Transistor`, `IC`, …), from `scripts/common.py:class_folder(typeid)` for this part's typeid.
  This is the same Class that names its library-repo folder, so the symbol carries it too.
- **Read from the datasheet** (don't just echo given text — open the PDF and fill the real,
  verified values): `Value` = the **value only** in shorthand (e.g. `1u`, `12p`, `10k` — no
  package), plus `Manufacturer`, `Manufacturer Part`, `Operating Temperature`, `Tolerance`,
  `ROHS`, `Datasheet`, and `Process` by inference from the package.
- **Leave blank for now** — `Manufacturer 2` / `Manufacturer Part 2` (the second source). Don't
  populate these by default; they stay hidden in Altium until filled later. (An optional
  cross-reference search to find a second source is documented in
  `references/schlib_parameters.md` but is currently off — only do it if the engineer asks.)
- **Fill without pausing** — the `.SchLib` task is non-interactive, so don't stop to ask. The
  only genuinely non-derivable field is `Vecmocon Part Code` (internal): use it if the engineer
  already supplied it in the request, otherwise leave it blank (the SOP hides blank parameters)
  and note the gap in your summary rather than blocking on a question.

Leave any genuinely-unknown field blank — the SOP hides blank parameters, so a gap simply stays
empty until filled. The full method for the second-source search is in
`references/schlib_parameters.md`.

Collect the values into a `params.json` and write them into the symbol:

```bash
python scripts/schlib_write.py --schlib <in>.SchLib --params params.json --out <stage>/<tag>/<sym>.SchLib
```

Deliver the resulting `.SchLib`; the engineer opens it in Altium once to confirm it loads, then
**Saves to Server** with a revision note. The full parameter set, each value's source, the
`params.json` shape (incl. the `remove` list), and the mini-stream size caveat are in
`references/schlib_parameters.md` — read it before building the parameter set. If a file doesn't
round-trip, fall back to `scripts/altium_params.py` (emits an Altium DXP script to apply the same
parameters from inside Altium). Always have the engineer confirm the file opens in Altium — the
skill writes Altium's own binary format, so Altium is the final validator.

### Fill the component's Excel and push — automatically, no verification loop

The datasheet values you just read for the symbol belong in that component's per-part Excel
workbook too, so fill them in the **same pass and push the result without asking**. This is a
deliberate exception to the skill's usual "verify before Gitea" rule: when the engineer hands
over a symbol for the `.SchLib` task, they want the library entry brought fully up to date in
one shot — the Description and every parameter written into the Excel, the updated symbol saved
beside it, and the whole thing pushed — not a round of confirmation questions. The engineer is
already reviewing the symbol in Altium, so a separate spreadsheet verification loop adds delay
without adding safety. The one check that still stands is the symbol/footprint-vs-part match: if
the symbol clearly isn't this component, stop and flag it rather than pushing the wrong part.

1. **Fill the Excel automatically.** Reuse the values you already read for the symbol to build
   `part.json` — with `Description` built to `references/description_format.md` and every
   parameter the datasheet states — and fill the per-part sheet **directly, skipping the human
   verification loop (step 5)**. Do this inside a checkout of the library repo so it can be
   pushed; for a part already in Gitea, locate it with `find-part` exactly as in *Updating an
   existing part*, and re-derive the design columns from the symbol/footprint already in the
   folder so they carry through unchanged:

   ```bash
   python scripts/gitea_components.py checkout --dest work/
   python scripts/gitea_components.py find-part --mpn <MPN> --make <make> --root work/ --json
   python scripts/altium_refs.py design \
       --symbol work/<Class>/<tag>/<sym>.SchLib \
       --footprint work/<Class>/<tag>/<footprint>.PcbLib > design.json
   python scripts/fill_templates.py part.json \
       --template assets/template/template.xlsx --dest work/<Class>/<tag>/ --design design.json
   ```

   (If `find-part` returns `NOT FOUND`, the part isn't in Gitea yet — assemble the folder as a
   new part per steps 4–7, still without the verification loop, then push with `push-part`.)

2. **Drop in the updated symbol and push — no confirmation.** Copy the `.SchLib` you wrote with
   `schlib_write.py` into the same part folder under its proper name, then push the updated part
   — the symbol and the freshly filled Excel together — automatically:

   ```bash
   cp <stage>/<tag>/<sym>.SchLib work/<Class>/<tag>/<sym>.SchLib
   python scripts/gitea_components.py commit-push --root work/ \
       --message "update <tag>: fill parameters + symbol (by <operator name>)" \
       --author "<operator name> <<operator email>>"
   ```

   Pushing without asking is consistent with the skill's standing rule that pushing is automatic;
   what's new here is that the Excel fill is automatic too. Tell the user which parameters you
   filled, that the symbol was updated, and where in Gitea it landed. (A part-data fill isn't a
   template change, so nothing version-bumps and the changelog is untouched.)

## Per-typeid versioning

Versioning is **per typeid**, not global. Each typeid carries its own `template_version` and
`skill_version` in `assets/template/versions.json` (both start at 1). When a parameter is
added to a typeid, that typeid gets a new template, so its `template_version` bumps — and on
the back of that its `skill_version` bumps too (v1→v2). **Only that typeid moves**; every
other typeid keeps its versions. Those two numbers are exactly what `fill_templates` stamps
into that typeid's rows (cols B and C), so a row always records the template/skill version it
was built against. `append_parameter.py` does the bump; `common.py` is the single source for
reading and writing these numbers.

## The changelog

`append_parameter.py` maintains one **global** changelog as an Excel workbook at
`assets/CHANGELOG.xlsx` (sheet `Changelog`, styled green header). Every time a
typeid's template/version changes, one row is appended with columns
**Date | Typeid | Skill Version | Template Version | Description** — the version columns hold
the new versions, and Description is your note (or the parameter(s) added if you gave none).

The changelog lives in the **skill repo in Gitea** as well, and it is **cumulative from the
first change onward**. Two things keep it that way: at the start of a run `pull-skill` (step 0)
brings the current changelog down so a new change appends to the full history, and on push
`push-skill` **merges** the new local rows onto the changelog already in Gitea — appended,
never overwritten. So the Gitea copy is the growing, authoritative history across machines and
sessions; the merged file is copied back locally so the two stay in sync. If you ever see the
Gitea changelog with only the latest change, it means step 0 (`pull-skill`) was skipped.

## Backfilling existing parts

When the user wants a newly-added parameter applied to parts of that typeid already in Gitea:

```bash
python scripts/gitea_components.py checkout --dest work/
python scripts/gitea_components.py list-type --typeid <typeid> --root work/ --json
```

`list-type` lists every existing part of that typeid with the files in its folder — including
its datasheet, which is co-located. For each one: read that datasheet, re-extract the values
(including the new parameter), and rebuild its per-part sheet in place:

```bash
python scripts/fill_templates.py <that_part>.json \
    --template assets/template/template.xlsx --dest work/<Class>/<that_tag>/
```

Because `fill_templates` uses the current template and current versions, each rebuilt sheet
picks up the new column and the bumped version automatically. When all are done, push once
and tell the user the previous sheets were updated:

```bash
python scripts/gitea_components.py commit-push --root work/ --message "backfill <param> into <typeid>"
```

## Updating an existing part

When the duplicate check finds the part (or the user asks to revise one that's already in
Gitea), you're **editing a part in place** rather than assembling a new one. The mechanics are
the same edit-in-a-checkout pattern as backfill — the difference is you're changing one part's
own data, not applying a template change across a whole typeid. The guiding rule doesn't
change: nothing is overwritten until the engineer has verified the new version.

1. **Locate the part in a checkout you can commit.** Clone the library repo, then find the
   part's folder and typeid (recovered from its tag):

   ```bash
   python scripts/gitea_components.py checkout --dest work/
   python scripts/gitea_components.py find-part --mpn <MPN> --make <make> --root work/ --json
   ```

   `find-part` returns the part's Class, tag, typeid, the editable folder path under `work/`,
   and the files in it (its current `<tag>.xlsx`, datasheet, symbol, footprint). If it prints
   `NOT FOUND` (exit 4), the part isn't actually there — treat it as a **new** part and go back
   to the normal add flow from step 2.

2. **Decide with the user what's changing.** A part update can revise any of: the **parameter
   values** (re-read the datasheet, or a corrected/newer one), the **symbol/footprint**, or the
   **datasheet PDF** itself. Ask which, so you only touch what's meant to change and leave the
   rest of the folder intact.

3. **Apply the change in place, in `work/<Class>/<tag>/`.** A key thing to understand first:
   `fill_templates` **rewrites the whole data row**, so it fills the four design columns
   (`Library Ref/Path`, `Footprint Ref/Path`) from the `--design` map you give it — and leaves
   them **blank if you don't**. When you rebuild a sheet, always re-supply the design values, or
   you'll silently wipe the symbol/footprint refs that were already there. The symbol and
   footprint files live in the part folder, so re-deriving them is cheap: point `altium_refs`
   at whatever the folder will hold **after** your change.

   - **Values** (re-read the datasheet, or a corrected/newer one) → read the current
     `<tag>.xlsx` and the folder's datasheet so you start from what's there, re-extract into a
     fresh `part.json` (Description still built to `references/description_format.md`),
     re-derive the design columns from the folder's existing symbol/footprint, and rebuild the
     sheet in place **with `--design`**:

     ```bash
     python scripts/altium_refs.py design \
         --symbol work/<Class>/<tag>/<symbol>.SchLib \
         --footprint work/<Class>/<tag>/<footprint>.PcbLib > design.json
     python scripts/fill_templates.py part.json \
         --template assets/template/template.xlsx --dest work/<Class>/<tag>/ --design design.json
     ```

     Because `fill_templates` reads the **current** template and versions, the rebuilt sheet
     keeps this typeid's version stamp (a part-data fix isn't a template change, so nothing
     bumps) and picks up any columns the typeid has gained — while the `--design` map carries
     the existing symbol/footprint refs through unchanged. (If a part somehow has no
     symbol/footprint yet, there's nothing to preserve — rebuild without `--design`.)
   - **Symbol/footprint** → copy the new `.SchLib`/`.PcbLib` into the folder under their proper
     names (replacing the old ones), then re-derive against the **new** files and rebuild with
     `--design` exactly as above (this is step 6 of the add flow). Still flag a genuine
     symbol/footprint-vs-part misma