Datasheet Lens

datasheet-lens

datasheet-lens is a central store for the datasheets of electronic components. It keeps each datasheet one time and connects it to the projects that use it. Thus each person and each AI agent of a project uses the same correct documents.

• Electronics design. The project file datasheet-lens.toml in the repository of a design holds the parts of the design and their datasheets. datasheet-lens keeps this list the same as the parts of the CAD project (KiCad and other EDA tools).
• Software and firmware. The developers and their AI agents get the same datasheets as the hardware team: the same document and revision, not a copy from an unknown source.
• One source for the two. The hardware design and the software can use one project file, or each a project file with the same parts. The store identifies each PDF by its SHA-256, thus the two projects use the same document.
• Part selection. datasheet-lens asks the official APIs of the distributors (Mouser, DigiKey) and an optional local copy of the JLCPCB parts library. A parametric search finds new parts and replacement parts by their parameters. For each part, the tool gives the stock, the prices, the lifecycle state and the links to the datasheet, the symbol, the footprint and the 3D model. The values that the design needs come from the datasheet.

An LLM agent reads the datasheets through an MCP server. The tool does not convert a datasheet to text. A conversion makes errors that look correct: lost superscripts, merged table rows, shifted columns, wrong values from graphs. datasheet-lens builds an index to find the content, and gives the original pages and regions to the model on demand. The model reads only the parts that the work needs, and reads each value from the original.

Status: in development (version 0.4). The tools work and have tests. The interfaces can change.

Features

• Drill-down into a document. An index (outline, table and figure captions, page quality), a text search, a page map with element IDs, and images of an element, a region, a caption ("Table 57", with docling also when the table continues on more pages) or a full page at 300 to 600 dpi.
• Central store, shared by all projects. Each user has one store (default ~/.datasheet-lens) for all design projects. Each PDF is stored one time (SHA-256), with its index, its element map, its parts and the facts that sessions read from it. A datasheet that one project added is at once available to each other project: it is not downloaded, indexed or read again. A part can have a datasheet, a manual and errata.
• Facts. A value that a session read is saved with its source (document, page, element), so that a later session finds it.
• Project file. datasheet-lens.toml in the repository of a design holds the parts of the design and their documents. The team gets it with the repository. project_check compares it with the parts of the CAD project.
• Distributors. The ordering codes of a datasheet, and for each orderable MPN the lifecycle state, the stock and the prices from the official APIs of Mouser and DigiKey. No scraping. distributor_status tells the services of each distributor, for example which one has a parametric search.
• JLCPCB assembly. An optional local copy of the JLCPCB parts library: the JLCPCB stock for the assembly and the library class (Basic, Preferred, Extended) of each part. The tool marks a part with no stock NOT IN STOCK, and gives replacements with stock and no loading fee (the same MPN; resistors, capacitors and inductors with the same parameters). project_check compares the JLCPCB (LCSC) number of each symbol with the purchase source and with the library.
• Parametric search. Find new parts and replacement parts by their parameters at DigiKey or in the JLCPCB parts library, for example "N-channel MOSFET, Vdss 20 V to 40 V, gate drive 2.5 V, package 3x3". DigiKey keeps one value of a parameter at its own conditions: the result marks a filter that its data cannot decide (RDS(on) at a gate voltage of 2.5 V) NOT APPLIED, and the agent reads that value in the datasheet. The JLCPCB library lists more points of a value, and the tool applies such a condition to them.
• Take a found part. adopt takes a part of a search in one step: its datasheet (from the site of the manufacturer first), the part, and its purchase source (the source and its part number). The availability check then asks for that number.
• Inbox. A PDF file that a person downloads goes into the folder _inbox of the project. sync gives it to the project parts that it agrees with.
• Links to datasheets and CAD files. For each MPN, the links to the datasheet, the symbol, the footprint and the 3D model (Component Search Engine, SnapMagic, Ultra Librarian). With DigiKey, also the direct links to the models of the part. The user opens the links: datasheet-lens does not download the CAD files.
• Team server (optional). One shared store for a team: the documents, parts, facts and the index and element map of each document. Each person keeps a local store that works also with no connection, and that synchronizes with the server. The server (datasheet-lens[server]) has accounts with roles and tokens, and a setup wizard installs it with PostgreSQL, the Garage object store, nginx and a Let's Encrypt certificate.

Typical uses

datasheet-lens helps to manage the input documents of a design project, and to keep them in the repository. It keeps the BOM equal to the CAD project. It lets the agent check the BOM, and check the design against the original datasheets.

• Keep the datasheets of a design complete and in git, the same for each person of the team.
• Compare the project with the parts of the CAD project: missing, extra and different parts.
• Select the concrete orderable MPN of a base part, and make sure that it can be ordered.
• Find new parts or replacement parts by their parameters, then check the candidates against their datasheets.
• Get the links to the datasheet, the symbol, the footprint and the 3D model of a part.
• Review a schematic against the datasheets: pins, absolute maximum ratings, logic levels, application circuits.
• Compare a footprint with the package drawing of the datasheet.
• Read register maps, bit fields and timing values for firmware, and keep them as facts with their source.
• Use the same parts in more projects: the datasheets and the facts of one project are at once available in each other project of the same user.

datasheet-lens does not read the schematic itself. The parts come from the CAD tool, its MCP server or a BOM file. See doc/use-cases.md for the steps of each use.

Installation

datasheet-lens needs Python 3.11 or newer. It works on Linux, macOS and Windows.

pipx install datasheet-lens

datasheet-lens init

datasheet-lens init makes the central store (default ~/.datasheet-lens, or the folder in the environment variable DATASHEET_LENS_HOME). It can also install docling, which gives a better element map (tables and figures). docling is optional: it needs some GB of disk. Without it, the tool uses the text layer.

Register the MCP server (stdio) in Claude Code:

claude mcp add --scope user datasheet-lens -- datasheet-lens-mcp

For a different MCP client, set the command datasheet-lens-mcp with no arguments. The server gives its instructions to the agent. See doc/installation.md and doc/mcp-server.md.

Quick start

In the root folder of the repository of the design:

datasheet-lens project init     # the project file, and a block in AGENTS.md, CLAUDE.md

datasheet-lens add PATH|URL # add a datasheet; it proposes the MPN of the part datasheet-lens sync # copy the documents into the project folder, and give the

PDF files of datasheets/_inbox/ to their parts

datasheet-lens check BOM.csv # compare the project with a BOM of the CAD project

The agent uses the same functions through the MCP server. The block in AGENTS.md or CLAUDE.md tells the agent the procedure. project init changes only the files that exist: make one of them first if you want the block.

All commands and options are in doc/cli.md.

Each user has a personal API key for each distributor. Get a free Mouser key at the Mouser API Hub (the Search API key, not the Cart API key), then run datasheet-lens key mouser. Get a free DigiKey key at developer.digikey.com. The key is a Client ID and a Client Secret of a production app. Then run datasheet-lens key digikey. If you set a distributor list before, add DigiKey to it: datasheet-lens dist mouser digikey. See doc/distributors.md.

Documentation

| [doc