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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Data access / search

Seller Toolbelt

Check and fix Amazon, eBay and Etsy product images, calculate marketplace fees, look up barcodes.

Checks passed
12 / 22

2 failed · 8 not measured

Median response
123 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
11

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 123 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name sellertoolbelt.

  • Pass
    Lists tools

    tools/list returned 11 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 123 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 123 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Fail
    Parameters documented

    24 of 43 parameters have a description (56%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-10-18T17:12:31.974875Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Seller Toolbelt

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http seller-toolbelt https://sellertoolbelt.com/api/mcp

Capabilities

Tools 11

add_watermark

Stamps text (e.g. "© Your Brand") on an image in a corner, the centre, or tiled diagonally. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered
calculate_marketplace_fees

Computes selling fees, net profit, margin and ROI for one sale on Amazon, eBay or Etsy from the sale price, shipping and costs. Category sets the default fee rate: amazon: default (15%), electronics (8%), computers (7%), clothing (17%), home (15%), toys (15%), books (15%); ebay: default (13.25%), electronics (9%), books (14.95%), clothing (13.25%); etsy: default (6.5%). Rates are 2026 estimates and vary by region; pass fee_rate_percent to override. Currency-agnostic. Free.

Discovered
change_background_color

Removes the background and places the product on a solid colour: white, light_gray, gray, black, beige, studio_blue, soft_pink, or custom with hex. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered
check_listing_image

Deterministically checks whether a product photo meets the main-image requirements of Amazon, eBay or Etsy (pure white background, product fill, minimum resolution, file format, colour space, borders, aspect ratio, sharpness, stray text/watermarks). Measured from the actual pixels, not guessed by a vision model. Returns pass / warn / fail with a reason per rule. Use before uploading a listing image. Free.

Discovered
convert_image

Re-encodes an image as jpeg, png, webp, avif at a chosen quality, to change format or shrink file size. JPEG flattens transparency to white. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered
generate_qr_code

Generates a QR code image (PNG) or SVG markup for any text or URL, e.g. for packaging inserts, product labels or invoices. Free.

Discovered
get_result

Checks a job created by one of the image tools. Returns download_url once it is unlocked (API-key jobs are paid up front; anonymous ones by a human via unlock_url). Otherwise returns the status, preview_url and unlock_url. Never charges. Anonymous results expire 24h after creation unless claimed.

Discovered
lookup_barcode

Finds product details (title, brand, category, image, description) for a UPC, EAN or GTIN barcode, using open product catalogs (strong for UK/EU groceries, drinks and cosmetics). Free.

Discovered
make_compliant_main_image

Removes the background, centres and scales the product on pure white, sizes and encodes it to the marketplace spec (Amazon, eBay or Etsy), then re-checks the result and returns the per-rule verdict as proof. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered
remove_background

Cuts the product out of its background and returns a transparent PNG. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered
resize_for_marketplace

Fits the image onto an exact canvas, padding with white: amazon (2000×2000), ebay (1600×1600), etsy (2000×2000), square (1080×1080), instagram_portrait (1080×1350), story (1080×1920), or custom width/height. Without an API key: returns a free watermarked preview (≤700px) plus unlock_url, which a human opens to download the full-resolution file for site credits (then call get_result). With an API key (Authorization: Bearer stb_…): returns download_url for the full-resolution file directly and charges the key owner's credits when the job starts, refunded automatically if processing fails. Retrying a call creates and charges a new job — use get_result to fetch an earlier one.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected123 ms11