ISSN digit shape is answering right now. Last checked 14 min ago. It exposes 31 tools. Last commit 23 Sep 2026.
ISSN digit shape
Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 18 September 2026. No other catalogue keeps this.
Everything else answered, so this is steady rather than shaky. We check every 15 minutes, which is how a one-off gets told apart from the start of a pattern, and how you hear about the next one within the hour instead of from your users.
Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 14 min ago.
claude mcp add issn-ok --transport http https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp
https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp
[mcp_servers.issn-ok]
url = "https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp"
{
"mcpServers": {
"issn-ok": {
"url": "https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp"
}
}
}
{
"servers": {
"issn-ok": {
"type": "http",
"url": "https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp"
}
}
}
Read directly from the server with tools/list, grouped by what they act on.
If a tool disappears, we record the date.
agent-ads-index
agent-tool-index
fetch-status
status-catalog
browser-url-ok
calc-eval
citation
compatibility
domain-shape
figma-url-shape
file-path-ok
hn-front-count
geo-hint
github-repo-shape
iana-zones
inspect-robots
issn-ok
jira-key-shape
search-query-len
lib-docs-hint
memory-key-count
normalize-url
people-search-index
playwright-url-ok
think-steps
timezone
utc-time
validate-json
weather-hint
web-fetch
wiki-title-ok
| URL | Transport | State | Latency | Checked |
|---|---|---|---|---|
| https://agent-observatory-sensor.nolimit-observatory.workers.dev/s/issn-ok/mcp | streamable-http | answering | 62 ms | 14 min ago |
ISBN digit shape
EAN/UPC digit shape
ISSN shape, value discarded
ISBN-13 digit shape, value discarded
ISNI 16-digit shape, value discarded
ISBN-10 digit shape, value discarded
ISSN URN shape, value discarded
BSB 6-digit shape, value discarded
Answers built from our own checks of this server.