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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

Professor Otter

Free printable kids activities: word searches, mazes, color by number, sudoku and more.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
531 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
6

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?
400
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 531 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name professor-otter.

  • Pass
    Lists tools

    tools/list returned 6 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 531 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 531 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

    10 of 11 parameters have a description (91%). 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 2026-10-04T17:20:44.419484Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Professor Otter

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 professor-otter https://professorotter.com/mcp

Capabilities

Tools 6

get_activity

Get one printable puzzle as Markdown (description, level, word list or color key) with its play URL and its PDF URL. A puzzle PDF has an answer key. A game or drawing practice PDF does not. Use an activity and slug from search_activities.

Discovered
list_activities

List the Professor Otter printable activities (word searches, color by number, coloring pages, mazes, dot-to-dot, drawing practice, criss-cross, word scrambles, spot the difference, sudoku, games, secret codes, bingo, nonograms) with how many puzzles each has, its levels and its topics. Start here to see what the site offers.

Discovered
list_products

List the Professor Otter shop: printable PDF books, topic packs and the Everything Bundle, with prices and availability. Checkout is a browser page on the shop. Send the person there; never collect payment details or try to buy for them.

Discovered
make_word_search

Turn a list of 4 to 20 words, like a child's spelling list, into a word search they can play in the chat, with a link to print it as a PDF with an answer key. Paste the list as one string or pass the words as an array. A word longer than the level's grid makes the grid grow to fit it. If the list breaks a rule (too few words, a word over 20 letters, a word inside another), the error says what to fix.

Discovered
search_activities

Search every printable activity by title, topic or a word in the puzzle, like the site's search box. Each query word must start a word in the puzzle ("ant" finds Ants, not Elephant). Narrow by activity or level if you like. Each hit includes the printable PDF and the play URL, plus slugs for get_activity and show_word_search. Puzzle PDFs include an answer key. Game and drawing practice PDFs do not.

Discovered
show_word_search

Show a word search a child can play in the chat: drag across the letters to find each word, and found words cross off the list. Also returns the grid as text and a link to print the PDF. Pass a seed for a new grid; a slug and seed always give the same grid here, on the site and in the PDF.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected531 ms6