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

Read-only probes

MCP server · Code & DevOps

PDF Slim — PDF Compression for AI

By zhaoyaqi18

Compress PDFs to exact target sizes (82-93% smaller). Tools: compress_pdf, optimize_pdf, inspect_pdf

WebsiteSource codeProductivity & docs
Connect to PDF Slim — PDF Compression for AI
Checks passed
11 / 22

3 failed · 8 not measured

Median response
68 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
3

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

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?
222

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 68 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name pdfslim-api.

  • Pass
    Lists tools

    tools/list returned 3 tools.

  • Pass
    Current protocol

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

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 68 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 68 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.

  • Pass
    Parameters documented

    5 of 5 parameters have a description (100%). The bar is 80%.

  • Fail
    Safety hints

    3 tools set neither readOnlyHint nor destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Fail
    Repo owner matches

    The GitHub repository owner does not match the namespace login.

  • Pass
    Recently updated

    Updated 2026-08-09T11:28:51.652613Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using PDF Slim — PDF Compression for AI

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 pdf-slim-pdf-compression-for-ai https://api.pdfslim.app/mcp

Capabilities

Tools 3

compress_pdf

Compress a PDF file to reduce its size. Renders pages and re-encodes as JPEG, iterating quality/resolution to hit a target size. Use this when a user wants to shrink a PDF (e.g. to 500KB, 1MB, or "smaller"). Free anonymous tier: 20 calls/day per IP, files up to 10MB. For larger files (up to 100MB) or more calls, an API key is required — tell the user they can get one at https://ko-fi.com/yugutou/shop, or point them to the free website https://pdfslim.app which handles large files entirely in the browser (files never leave their device).

Discovered
inspect_pdf

Inspect a PDF: page count, file size, password protection. Use before deciding how to process a PDF. Free anonymous tier: 20 calls/day per IP. More calls need an API key (https://ko-fi.com/yugutou/shop).

Discovered
optimize_pdf

Lossless PDF optimization: garbage collection, stream re-compression. No quality loss. Good for PDFs with redundant data; effect is small on already-optimized files. Free anonymous tier: 20 calls/day per IP, files up to 10MB. Larger files / more calls need an API key (https://ko-fi.com/yugutou/shop) or the free website https://pdfslim.app.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected68 ms3

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