Mouser Electronics Parts Search & Analysis

Mouser is the secondary source for prototype orders — use when DigiKey is out of stock or has worse pricing. For production orders, see lcsc/jlcpcb. For BOM management and export workflows, see bom. For datasheets, prefer DigiKey's API (direct PDF links) — Mouser blocks automated PDF downloads.

API Credential Setup

Mouser uses simple API key authentication — no OAuth, no tokens, no callback URLs. The Search API key is a UUID passed as a query parameter.

Getting Your API Key

1. Go to mouser.com → My Mouser → My Account
2. Under "APIs" section, click "Manage"
3. Register for Search API key — this is the one needed for part lookups and datasheet downloads
4. Search API keys may require approval (status shows "pending authorization" initially)

Setting Credentials

Set the environment variable before running the scripts:

export MOUSER_SEARCH_API_KEY=your-search-api-key-uuid

If credentials are stored in a central secrets file (e.g., ~/.config/secrets.env), load them first:

export $(grep -v '^#' ~/.config/secrets.env | grep -v '^$' | xargs)

Mouser Search API Reference

All search endpoints use the Search API key as a query parameter: ?apiKey=<key>. Content-Type is application/json for all POST requests.

V1 Endpoints

Keyword Search

POST /api/v1/search/keyword?apiKey=<key>

{
  "SearchByKeywordRequest": {
    "keyword": "100nF 0402 ceramic capacitor",
    "records": 50,
    "startingRecord": 0,
    "searchOptions": "InStock"
  }
}

• searchOptions: "None" | "Rohs" | "InStock" | "RohsAndInStock"
• records: max 50 per request
• startingRecord: offset for pagination

Part Number Search

POST /api/v1/search/partnumber?apiKey=<key>

{
  "SearchByPartRequest": {
    "mouserPartNumber": "GRM155R71C104KA88D|RC0402FR-0710KL",
    "partSearchOptions": "Exact"
  }
}

• Up to 10 part numbers, pipe-separated (|)
• Works with both Mouser part numbers AND manufacturer part numbers (MPNs)
• partSearchOptions: "Exact" | "BeginsWith" | "Contains"

V2 Endpoints

V2 adds manufacturer filtering and pagination by page number.

Keyword + Manufacturer Search

POST /api/v2/search/keywordandmanufacturer?apiKey=<key>

{
  "SearchByKeywordMfrNameRequest": {
    "keyword": "LMR51450",
    "manufacturerName": "Texas Instruments",
    "records": 25,
    "pageNumber": 1,
    "searchOptions": "InStock"
  }
}

Note: the wrapper object name is SearchByKeywordMfrNameRequest (not SearchByKeywordMfrRequest — the V1 name is deprecated).

Part Number + Manufacturer Search

POST /api/v2/search/partnumberandmanufacturer?apiKey=<key>

Manufacturer List

GET /api/v2/search/manufacturerlist?apiKey=<key>

Returns the full list of manufacturer names for use in filtered searches.

V1 Deprecated Endpoints

These still work but V2 equivalents are preferred:

• POST /api/v1/search/keywordandmanufacturer → use V2
• POST /api/v1/search/partnumberandmanufacturer → use V2
• GET /api/v1/search/manufacturerlist → use V2

Search Response Structure

All search endpoints return the same response format:

{
  "Errors": [],
  "SearchResults": {
    "NumberOfResult": 142,
    "Parts": [...]
  }
}

Key Part Fields

Field	Type	Description
MouserPartNumber	string	Mouser's internal part number (prefixed, e.g., 81-GRM155R71C104KA88)
ManufacturerPartNumber	string	Manufacturer's part number (MPN) — use for cross-distributor matching
Manufacturer	string	Manufacturer name
Description	string	Product description
Category	string	Product category
DataSheetUrl	string	URL to datasheet PDF (Mouser-hosted — see Datasheet section)
ProductDetailUrl	string	URL to Mouser product page
ImagePath	string	Product image URL
Availability	string	Human-readable stock text (e.g., "2648712 In Stock")
AvailabilityInStock	string	Numeric stock quantity (as string)
AvailabilityOnOrder	array	Incoming stock: [{Quantity, Date}]
LeadTime	string	Factory lead time (e.g., "84 Days")
LifecycleStatus	string|null	"New Product", "End of Life", etc.
IsDiscontinued	string	"true" or "false" (string, not boolean)
SuggestedReplacement	string	Replacement MPN if discontinued
Min	string	Minimum order quantity (as string)
Mult	string	Order multiple (as string)
Reeling	bool	Tape-and-reel packaging available
ROHSStatus	string	RoHS compliance status
PriceBreaks	array	Tiered pricing: [{Quantity, Price, Currency}]
ProductAttributes	array	Parametric specs: [{AttributeName, AttributeValue}]
AlternatePackagings	array|null	Alternate packaging MPNs: [{APMfrPN}]
SurchargeMessages	array	Tariff/surcharge info: [{code, message}]
ProductCompliance	array	HTS codes, ECCN: [{ComplianceName, ComplianceValue}]
UnitWeightKg	object	{UnitWeight: <float>} in kg

Quirks and Gotchas

• Price is a string with currency symbol: "$0.10", not a float. Parse it before comparing.
• Stock is a string: AvailabilityInStock returns "2648712" not 2648712.
• IsDiscontinued is a string: "true" or "false", not boolean.
• Mouser part numbers have prefixes: 81-GRM155R71C104KA88 — the prefix is Mouser-specific. Use ManufacturerPartNumber for cross-referencing.
• V2 wrapper names differ from V1: V2 uses SearchByKeywordMfrNameRequest, not SearchByKeywordMfrRequest.
• Tariff info: SurchargeMessages may contain US tariff percentages — useful for cost estimation.
• On-order data: AvailabilityOnOrder shows incoming stock quantities and expected dates.

Datasheet Download & Sync

Mouser's DataSheetUrl field points to Mouser-hosted URLs (mouser.com/datasheet/...). These URLs block automated downloads — they return an HTML "Access denied" page when fetched with Python/curl/wget, even with browser User-Agent headers. The download scripts handle this by trying alternative manufacturer sources.

Datasheet Directory Sync

Use sync_datasheets_mouser.py to maintain a datasheets/ directory alongside a KiCad project. Same workflow and index.json format as the DigiKey skill.

# Sync datasheets for a KiCad project
python3 <skill-path>/scripts/sync_datasheets_mouser.py <file.kicad_sch>

# Preview what would be downloaded
python3 <skill-path>/scripts/sync_datasheets_mouser.py <file.kicad_sch> --dry-run

# Retry previously failed downloads
python3 <skill-path>/scripts/sync_datasheets_mouser.py <file.kicad_sch> --force

# Custom output directory
python3 <skill-path>/scripts/sync_datasheets_mouser.py <file.kicad_sch> -o ./my-datasheets

Single Datasheet Download

Use fetch_datasheet_mouser.py for one-off downloads.

# Search by MPN (uses Mouser API)
python3 <skill-path>/scripts/fetch_datasheet_mouser.py --search "TPS61023DRLR" -o datasheet.pdf

# Direct URL download
python3 <skill-path>/scripts/fetch_datasheet_mouser.py "https://example.com/datasheet.pdf" -o datasheet.pdf

# JSON output
python3 <skill-path>/scripts/fetch_datasheet_mouser.py --search "ADP1706" --json

Download Strategy

The scripts try multiple sources in order:

1. Schematic URL — uses the datasheet URL embedded in the KiCad symbol (sync only)
2. Mouser API search — gets the DataSheetUrl from the API response
3. Alternative manufacturer sources — tries known URL patterns for major manufacturers (TI, Microchip, etc.) when the Mouser URL is blocked
4. Headless browser fallback — if playwright is installed, uses headless Chromium as a last resort

When all methods fail, provide the ProductDetailUrl to the user so they can download from the Mouser product page in their browser.

Web Search Fallback

If no API key is available, search Mouser via WebFetch:

• Search URL: https://www.mouser.com/c/?q=<query>
• Product pages contain full specs, pricing tiers, stock, datasheets
• WebFetch results from Mouser can be noisy (JS-heavy pages)

Include key parameters in the query:

• Passives: value, package (0402/0603/0805), tolerance, voltage/power rating, dielectric (C0G/X7R)
• ICs: part number or function, package (QFN/SOIC/TSSOP), key specs (voltage, current, interface)
• Connectors: type (USB-C, JST-PH), pin count, pitch, mounting (SMD/THT), orientation

Tips

• Pipe-separate up to 10 part numbers in a single PartNumber search for batch lookups
• Min and Mult fields matter — some parts have minimum order qty or must be ordered in multiples
• SurchargeMessages may include US tariff percentages — factor into cost estimates
• AvailabilityOnOrder shows incoming stock with expected dates
• Check IsDiscontinued and LifecycleStatus before selecting parts

Platform Guidance

• Claude Code: Present part search results as tables. Use AskUserQuestion to confirm part selection before adding to BOM.
• Codex/OpenCode: Present results as numbered options. Ask user to type selection number.
• CLI: All part search and sourcing operations available via circuit-weaver subcommands.