电子元器件数据查询MCP服务

PCB Parts MCP Server

MCP server that gives Claude, Cursor, and other AI coding assistants electronic component data from JLCPCB, Mouser, and DigiKey: parametric search over 630K+ in-stock JLCPCB parts, live stock and pricing on all three, KiCad footprints, reference boards, sensor picks, and design rules. No API key required.

Website: pcbparts.dev

Features

• Three distributors: search JLCPCB, and look up live price and stock for specific parts on Mouser and DigiKey
• Parametric search: Filter by electrical specs (Vgs(th) < 2V, Rds(on) < 10mΩ, etc.)
• Smart query parsing: "10k 0603 1%" auto-parses into structured filters
• Find alternatives: Spec-aware compatibility checking for 120+ component types
• KiCad footprints: Download symbols and footprints via SamacSys
• Pinout data: Component pin information from EasyEDA symbols
• MPN lookup: Find JLCPCB equivalents by manufacturer part number
• Sensor recommendation: Find sensor ICs by what they measure, protocol, or platform (1,600+ sensors, 56 measure types)
• Reference boards: Search ~285 OSHW board schematics, IC neighborhoods, cross-board consensus for design patterns
• Design rules: 41 curated PCB design reference files covering power, protection, interfaces, MCUs, layout, and EMC
• 14 MCP tools
• No API key required for JLCPCB (Mouser/DigiKey optional)

Quick Start

Claude Code

claude mcp add -s user --transport http pcbparts https://pcbparts.dev/mcp

Optional — auto-approve all pcbparts tools in ~/.claude/settings.json:

{
  "permissions": {
    "allow": ["mcp__pcbparts__*"]
  }
}

Claude Desktop

Add via Settings → Connectors → "Add custom connector", or add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "pcbparts": {
      "type": "http",
      "url": "https://pcbparts.dev/mcp"
    }
  }
}

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "pcbparts": {
      "type": "http",
      "url": "https://pcbparts.dev/mcp"
    }
  }
}

VS Code

Add to .vscode/mcp.json:

{
  "servers": {
    "pcbparts": {
      "type": "http",
      "url": "https://pcbparts.dev/mcp"
    }
  }
}

Copilot for Xcode

Add to Extensions config:

{
  "mcpServers": {
    "pcbparts": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://pcbparts.dev/mcp"]
    }
  }
}

Available Tools

Typical workflow: get_design_rules / board_search + board_get(focus=IC) → jlc_search → jlc_get_part (datasheet, footprint) → jlc_find_alternatives → cse_get_kicad (KiCad files).

Tool descriptions include reply-field guidance: relaxed names omitted query words, a query-only library preference or a dropped part type; relaxed.dropped_filters lists parsed spec filters omitted by a part-number retry; parsed.adjusted_filters lists moved/omitted specs; ignored_filters explains unapplied/rare filters; hint suggests a next step on empty replies; when a search shortens a full part number (LM1117-3.3 searches LM1117), each result's mpn_match says whether it is the full part number, keeps its suffixes (same_suffix) or is another family member, those come in that order, and mpn_matches counts each; counts_complete=false means partial counts; valid_values lists accepted inputs on errors. In jlc_get_part, prices lists quantity tiers, datasheet links the datasheet, and has_easyeda_footprint=null means unknown (false means absent); MPN lookups return results and total. MPN replies that aren't exact matches add match (separators, packing, alias, alternative, lcsc or related) and matched_mpn; related replies add a note naming the part types returned and any part another manufacturer numbered after the original; an LCSC code given as mpn returns that part (lcsc). In alternatives, summary.found counts verified alternatives, unverified_alternatives need manual comparison, specs_unparseable lists specs not verified, and unchecked_requirements includes pinout/circuit checks still needed. In board_get, focus_match_type is exact, partial or ref matching; consensus.board_count counts compared boards, and passives_omitted counts hidden plain passives.

jlc_get_part(mpn=...) also finds a part spelled with different dashes or spaces (ERJ-2RKF2702X → ERJ2RKF2702X), with another reel or packing code from the same manufacturer (AD8630ARZ-REEL7 → AD8630ARZ), or written as a BOM entry with notes or alternatives (TL074 OP AMP, AMC1301 or AMC1302). It never substitutes a different temperature or performance grade. related results can span different part types (SSD1306 returns an OLED display and power inductors), so check them before choosing a part.

JLCPCB (Local DB + Live API)

Mouser (requires MOUSER_API_KEY)

DigiKey (requires DIGIKEY_CLIENT_ID + DIGIKEY_CLIENT_SECRET)

Sensor Recommendation (no key required)

Reference Boards (no key required)

Design Rules (no key required)

SamacSys (no key required)

search vs stock_check

Use jlc_search (default) for:

• Parametric filtering ("Vgs(th) < 2V", "voltage >= 25V")
• Smart query parsing ("10k 0603 1%" auto-detects value, package, tolerance)
• Most searches

Use jlc_stock_check only when you need:

• Real-time stock verification before ordering
• Out-of-stock or low-stock parts (stock < 10)
• The full catalog (7M+ parts; jlc_search covers the 630K+ with stock >= 10)

Library Types

Subcategory Aliases

Natural language names that map to JLCPCB subcategories (220+ aliases supported):

inductor, relay and diode each cover several subcategories (SMD, power, molded and through-hole inductors; signal, power, automotive, reed and latching relays; switching, general-purpose, Schottky, fast-recovery and SBR diodes).

A value in the query goes to the spec that part type lists: "5V relay" is the coil voltage, "3.3V LDO" the exact output, "12V buck converter" an output range covering 12V (with Topology Buck), "3.3V level shifter" a supply range covering 3.3V. "24V input 3.3V output" and "12V to 5V" set both sides of a regulator. If the part type lists no such spec, the value is left out and parsed.adjusted_filters says so; words that match no part together with the rest of the query are left out and relaxed says so; filters that can't be applied are listed in ignored_filters.

jlc_search defaults to 20 results; an explicit limit can request up to 100. Component replies omit description when nonempty specs already provide the detail. price_10 is removed from search, stock-check and part-detail replies; use the stated quantity tiers in jlc_get_part.prices.

packages (search/stock check) and manufacturers (stock check) accept a list, JSON array string, or one bare string. Values containing commas stay intact. Query package alternatives such as 100nF 25V capacitors in 0402 or 0603 apply an OR constraint, equivalent to packages=["0402", "0603"]; explicit package arguments take precedence.

Explicit spec_filters accept JSON arrays or JSON array strings, with text or numeric values. Attribute/alias names ignore case, => normalizes to >=, and unitless numbers use the attribute's base unit (V, A, ohms, F, H, Hz, W, mm or bytes; tolerance/ppm follow their named scale). Malformed lists/filters and invalid operators return an error with valid_values instead of removing constraints. Unknown library/sort enum values list their valid choices. Explicit unsupported or rare attributes are reported in ignored_filters with attribute_share and suggested real names; the reason distinguishes “not applied” (with the query-builder reason) from “applied, but few or none of these parts list it”, where results may be incomplete or empty. Rare valid constraints are retained. Gate Threshold and Vgs(th) both alias Gate Threshold Voltage (Vgs(th)) / Gate Threshold Voltage.

library_type_counts and no_fee_available describe the same matching population as total, after every spec and library restriction. Post-filter scans check at most 50,000 SQL candidates; if that cap is reached, counts_complete=false labels these counts and availability as applying only to checked matches.

Recovery hints use exposed calls such as jlc_search_help() and jlc_search_help(subcategory="MOSFETs"). Every returned design-rule key (for example power/ldo) can be passed back as get_design_rules(topic="power/ldo") for that exact file.

Board consensus pin choices use distinct-board votes: count is supporting boards and pct divides by consensus.board_count. Each choice adds boards (supporting slugs) and quantities (component occurrences per supporting board). Repeated components on a board do not add votes; the denominator includes all matching boards with an IC neighborhood.

Attribute Aliases

Short names for parametric spec filters:

Supply and output voltages are often ranges ("2.7V~5.5V"): = matches a range that includes the value, >= one that reaches it, <= one that goes down to it.

Use jlc_search_help(subcategory=...) to discover all filterable specs for any subcategory.

Query values accept u/µ/μ and Ω: 2.2µF, 10 kΩ, 4u7 (4.7uF, or 4.7uH in an inductor query), 6V3 (6.3V), and 1F. Resistance prefixes keep their case: 10M/10Meg/10MEG mean megaohms; 10m/10mOhm/10 milliohm mean milliohms. Query package 1005 means imperial 0402. Crystal/oscillator capacitance means Load Capacitance. Named comparisons such as 3.3V LDO quiescent current < 10µA, standby current < 10uA, Iq < 10uA, and schottky diode 1A Vf < 0.3V preserve the quantity and operator. Use a numeric limit for idle current; “low Iq” does not apply one. Unparsed numeric units such as 2.2qF stay in the text search, are listed in parsed.detected.unsupported_constraints, and are named as unapplied in relaxed.reason if the default relaxed retry drops them. Relaxation remains the default; pass strict=true to keep query words and parsed requirements, disable both text and library retries, and return an actionable error with no results for unsupported constraints (ignored_filters / parsed.adjusted_filters). Strict replies never contain relaxed. Shorthand rewrites do not alter model tokens or hyphen-connected suffixes such as AMS1117-3V3.

Compound buck-boost/buck boost topology is retained. Regulator input phrases (input up to 24V, Vin 24V, 24V max input, from 24V, up to 24V in) target the supply, separately from output voltage. 3.3V to 5V bidirectional level shifter checks Channel Type and VCCA/VCCB independently; verify bus and signal-standard compatibility in the datasheet. Through-hole mounting selects the through-hole resistor or leaded electrolytic category when the default is SMD-only.

motor driver covers all four motor-driver categories; dc motor driver/h-bridge, stepper driver, and bldc driver/esc select brushed DC, stepper, and BLDC respectively. Hobby-part aliases include USB PD/USB-PD, eFuse, fuel gauge (Monitoring IC), MEMS microphone, and polymer capacitor. supercap/supercapacitor is recognized as unavailable in this JLCPCB catalog and points to Mouser/DigiKey; general unknown-part-type handling is unchanged.

Memory sizes are minimum capacities: ESP32-S3 module 16MB flash 8MB PSRAM checks module N/R ordering codes, microcontroller 128KB flash checks Program Storage Size, and SPI flash 16MB still searches NOR flash. ESP32 modules with unknown memory codes cannot satisfy a memory constraint. An N-code without an R-code has known zero PSRAM, so it cannot satisfy a PSRAM minimum or replace a module requiring PSRAM.

Query words basic/basic part, preferred, and no assembly fee/no fee set the library filter; cheapest/lowest price select price sorting (within library tiers when prefer_no_fee=true). These appear in parsed.detected; explicit library_type and sort_by arguments win. Library choices have a schema enum, with case and no-fee normalized before validation. If a query-only library preference finds nothing, the default search retries without it and explains that the library preference was left out in relaxed.reason. An explicit library_type never relaxes. Stock-check and alternatives library arguments accept the same spellings; sort choices ignore case too.

Sensor filters accept 1-wire/one-wire as one_wire, and heart rate/blood oxygen as biometric. Sensor measures, protocols and platforms, and board tags, are validated against the local catalog; unknown values return an error with valid_values. ESP-IDF has no platform-support records in this catalog, so platform="esp-idf" reports the supported choices. Board tag usb-c maps to usb; tag matching ignores case and surrounding whitespace.

Package Expansion

Package filters auto-expand to include variants:

• "SOT-23" → includes SOT-23-3, SOT-23-3L, SOT-23(TO-236)
• "0603" → includes 1608 (metric equivalent)
• Specific packages like "QFN-24-EP(4x4)" are NOT expanded

find_alternatives

Finds alternatives checked against catalog compatibility rules (summary.found counts only verified alternatives). unverified_alternatives separately lists candidates missing a required match, with verification_status, unverified_requirements and unchecked_requirements; these require manual comparison. Unsupported categories continue to return similar_parts, with summary.found=0 and summary.similar_count.

1. Matches the primary spec (resistance, capacitance, etc.) and required specs. Missing or unparseable required matches cannot enter alternatives.
2. Checks connector contacts, mounting orientation and stated wire-to-board reference series; battery IC function; transistor polarity/count; and module chip identity. An empty ESP32 chip attribute can be inferred from its MPN. ESP32 N/R flash and PSRAM capacities must be at least the original's; unknown capacities are unverified.
3. Checks same-or-better ratings. Dropout, Vf and RDS(on) use test conditions when available. Unchecked secondary specs stay in specs_unparseable and unchecked_requirements and lower confidence.
4. Requires regulator input/output ranges to cover the original's full ranges. A scalar supply rating proves only the maximum; minimum input voltage remains unchecked. Regulator pinout and external-circuit requirements always need manual review, so regulator confidence is never high.
5. Ranks no-fee parts (basic/preferred) first. Within each fee tier, passives and crystals prefer the original package, then the existing stock/footprint/manufacturer/price score. Other packages remain available; same_package=true filters them out. Each verified/unverified list has its own limit (default 10, max 50).

Candidates come from live JLCPCB search and the daily local database. Rule checks establish catalog compatibility, not a guaranteed drop-in replacement; review datasheets and package_warning. An empty library_type="no_fee" result states how many verified extended matches were evaluated (summary.extended_count), rather than claiming no savings are possible. Counts are bounded by the candidate search, not catalog totals.

Use an LCSC C-code for lcsc; for an MPN, first use jlc_get_part(mpn=...). Project savings accept positive board_quantity and placements_per_board (both default 1). comparison.savings separates the one-time assembly_fee difference, unit_price_diff, component_quantity and order_total; the misleading total_per_unit field is removed. Fees include added as well as removed extended part types, assuming the original type is removed entirely and the replacement type is newly added to the order. Prices are qty-1 tier estimates; unknown prices leave unit/order savings null.

Supported: Resistors, capacitors, inductors, ferrite beads, MOSFETs, BJTs, diodes (all types), LEDs, optocouplers, crystals, oscillators, LDOs, DC-DC converters, voltage references, WiFi/BT/LoRa modules, switches, relays, connectors, and more (120+ subcategories).

Example Queries

"Find logic-level MOSFETs with Vgs(th) < 2V and Id >= 5A"
"100nF 25V capacitors in 0402 or 0603"
"Find alternatives for C82899 in basic library"
"STM32 microcontrollers with 10000+ stock"
"Look up TPS63020 stock and pricing on Mouser"
"Get KiCad footprint for ESP32-S3-WROOM-1"
"What sensor should I use to measure CO2 on ESPHome?"
"Recommend an IMU sensor with I2C interface"
"Show me boards that use the MCP73831 charger"
"How is the RP2040 typically used? What decoupling and crystal do real boards use?"
"Get the ESP32-S3 neighborhood on the Adafruit Feather"
"What are the design rules for USB-C?"
"Show me LDO design best practices"

API Details

• Endpoint: https://pcbparts.dev/mcp
• Transport: Streamable HTTP (stateless)
• Health: https://pcbparts.dev/health (status, version, EasyEDA footprint answers seeded and stored, CSE searches and KiCad parts stored, and each distributor's requests today)
• Usage stats: https://pcbparts.dev/mcp/stats (anonymous counts per UTC day, with totals for the days shown: calls per UTC hour, calls to each tool split into ok, similar_only (alternatives that returned only similar or unverified candidates to compare by hand), not_found, bad_request, rate_limited and failed, with the average time, which MCP apps connect, the number of distinct callers, and Mouser/DigiKey lookups sent, cached or turned away by the limits; the stats keep no IPs, queries or part numbers; the last 30 days, ?days=N for fewer)
• Rate limit: 100 requests/minute per IP
• Auth: None required

Self-Hosting

On pcbparts.dev, Mouser and DigiKey lookups share one API key each: 1,000 requests a day and 25 (Mouser) or 100 (DigiKey) a minute for everyone. Self-hosting with your own keys (MOUSER_API_KEY, DIGIKEY_CLIENT_ID/DIGIKEY_CLIENT_SECRET, free from Mouser's API hub and DigiKey's developer portal) gets you your own limits.

git clone https://github.com/Averyy/pcbparts-mcp
cd pcbparts-mcp
uv venv && uv pip install -e .
.venv/bin/python -m pcbparts_mcp.server  # http://localhost:8080/mcp

The server builds data/components.db only when it's missing. If yours is from before 0.6.0, rebuild it (.venv/bin/python scripts/build_database.py) to get the EasyEDA footprint seed; without it, footprint checks still work but each one asks EasyEDA. The server logs a warning if the database predates this version; rebuilding with the same command also fixes missing quiescent-current filter matches and slow MPN lookups.

Or with Docker:

docker compose up -d                                    # production (GHCR image)
docker compose -f docker-compose.local.yml up --build   # local dev (builds from source)

docker-compose.yml publishes the server on 127.0.0.1:8080 only, for a reverse proxy on the same host (pcbparts.dev runs Caddy in front of it). To reach it from other machines, change the port mapping to "8080:8080".

Building the image needs BuildKit, the default builder since Docker 23 and the one Compose v2 uses.

Environment Variables

LLM-Readable Documentation

An llms.txt file is available for LLMs and AI agents to quickly understand this service. See llmstxt.org for the spec.

Changelog

See CHANGELOG.md. Minor releases in 0.x can change replies; each lists what to check under Breaking.

Contributing

Issues and PRs welcome — see CONTRIBUTING.md for development setup, testing, and project conventions.

License

MIT

Links

• pcbparts.dev
• JLCPCB Parts Library
• MCP Protocol