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io.github.squidcode/tapwatermap

REMOTE · MCP.TAPWATERMAP.COM · SCANNED SEP 21

Query US tap-water quality from the EPA's SDWIS records — by city, system, or contaminant.

0 this week 84 Trust /100
Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security74
Transport & Reachability100
Schema Quality & AI Usability76
  • AI-judged instruction clarity (good).Pass
  • Tool/resource definitions use about 694 tokens (~69/item across 10 items; 10 tools + 0 resources), lean.Pass
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
  • No destabilizing schema changes in the last 30 days.Pass
Tool Coverage86
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 59% of tool parameters carry a description.Partial
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 10 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 11 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Install

How do I install the io.github.squidcode/tapwatermap MCP server?

io.github.squidcode/tapwatermap is a hosted endpoint at https://mcp.tapwatermap.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · mcp.tapwatermap.com

# add to Claude Code
claude mcp add --transport http squidcode-tapwatermap 'https://mcp.tapwatermap.com/mcp'
// .cursor/mcp.json
{
  "mcpServers": {
    "squidcode-tapwatermap": {
      "url": "https://mcp.tapwatermap.com/mcp"
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "squidcode-tapwatermap": {
      "type": "http",
      "url": "https://mcp.tapwatermap.com/mcp"
    }
  }
}
# ~/.codex/config.toml
[mcp_servers.squidcode-tapwatermap]
url = "https://mcp.tapwatermap.com/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "squidcode-tapwatermap": {
      "type": "remote",
      "url": "https://mcp.tapwatermap.com/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add squidcode-tapwatermap --url 'https://mcp.tapwatermap.com/mcp' --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  squidcode-tapwatermap:
    url: "https://mcp.tapwatermap.com/mcp"
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "squidcode-tapwatermap": {
      "Transport": "http",
      "Url": "https://mcp.tapwatermap.com/mcp"
    }
  }
}
# add to Vellum
assistant mcp add squidcode-tapwatermap -t streamable-http -u 'https://mcp.tapwatermap.com/mcp'
// mcp.json
{
  "mcpServers": {
    "squidcode-tapwatermap": {
      "type": "http",
      "url": "https://mcp.tapwatermap.com/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 26 Aug 26 +1
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 25 Aug 26 0
    • Stability: 0.97 → pass security
  • 24 Aug 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.

  • 11 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 31 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 30 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 27 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 26 Jul 26 0

    First indexed and scored.

Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 21 Sept 2026 · Probed https://mcp.tapwatermap.com/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=tapwatermap.com CN=WE1,O=Google Trust Services,C=US 21 Aug 2026 19 Nov 2026 ECDSA 256 ECDSA-SHA256 a34ce861754cf6370e8eb830a2140471
SANs: tapwatermap.com, mcp.tapwatermap.com, *.mcp.tapwatermap.com
CN=WE1,O=Google Trust Services,C=US (CA) CN=GTS Root R4,O=Google Trust Services LLC,C=US 13 Dec 2023 20 Feb 2029 ECDSA 256 ECDSA-SHA384 7ff31977972c224a76155d13b6d685e3
CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE 15 Nov 2023 28 Jan 2028 ECDSA 384 SHA256-RSA 7fe530bf331343bedd821610493d8a1b

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of mcp.tapwatermap.com. Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
com. present 19718 13 Verified
tapwatermap.com. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://mcp.tapwatermap.com/mcp Verified 200
http (plaintext) http://mcp.tapwatermap.com/mcp HTTPS enforced 301 https://mcp.tapwatermap.com/mcp
MCP tools · 10 exposed · ~643 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
compare_cities ~51

Compare the EPA records of several cities side by side. Pass cities as 'City, ST' strings.

NameTypeReqDescription
citiesarrayyese.g. ['Burlington, VT', 'Houston, TX']

No output schema declared.

No examples provided.

coverage_stats ~29

What TapWaterMap covers: states, cities, total EPA violation records, and the data quarter/date.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

explain_contaminant ~78

Plain-English explanation of an EPA contaminant by name or code: the EPA name, whether the EPA classifies it as health-based, and how often it appears in our records. Not medical advice.

NameTypeReqDescription
contaminantstringyesContaminant name or EPA code, e.g. 'TTHM' or '2950'.

No output schema declared.

No examples provided.

fetch ~64

Fetch the full plain-English EPA tap-water record for a city id (e.g. 'vt/burlington') returned by `search`. (ChatGPT/Deep-Research compatible.)

NameTypeReqDescription
idstringyesCity id like 'vt/burlington' (state/slug).

No output schema declared.

No examples provided.

find_cities ~121

Filter/rank cities across the dataset — e.g. cities in TX with open health-based violations, or cities with a specific contaminant. Returns ranked matches.

NameTypeReqDescription
contaminantstringOptional EPA contaminant code or name (use explain_contaminant to find a code).
healthBasedOnlyboolean
limitinteger
minPopulationinteger
openViolationsOnlybooleanOnly cities with violations not returned to compliance.
statestringOptional 2-letter state code.

No output schema declared.

No examples provided.

get_city_water ~94

The core tool: what the EPA has on record for a city's tap water — the active community water systems serving it, populations, sources, and violations (contaminant, health-based or not, dates, status, level vs limit when recorded). Plain-English, sourced, never a safety verdict.

NameTypeReqDescription
citystringyes
statestringyes2-letter state code, e.g. 'VT'.

No output schema declared.

No examples provided.

get_water_system ~50

EPA record for a single water system by its PWSID (e.g. 'VT0005053'): name, population served, source, and violations.

NameTypeReqDescription
pwsidstringyes

No output schema declared.

No examples provided.

list_state_cities ~34

List all covered cities in a state (with violation counts).

NameTypeReqDescription
statestringyes2-letter state code.

No output schema declared.

No examples provided.

search ~59

Search TapWaterMap for US cities by name. Returns matching cities with an id you can pass to `fetch`. (ChatGPT/Deep-Research compatible.)

NameTypeReqDescription
querystringyesCity name or partial name, e.g. 'Burlington'.

No output schema declared.

No examples provided.

search_cities ~63

Find covered US cities by name, optionally within a state. Returns counts + the page URL for each.

NameTypeReqDescription
limitinteger
querystringyes
statestringOptional 2-letter state code, e.g. 'TX'.

No output schema declared.

No examples provided.

Common questions

What is the io.github.squidcode/tapwatermap MCP server?

io.github.squidcode/tapwatermap is an MCP server listed in the public MCP registry as io.github.squidcode/tapwatermap. Query US tap-water quality from the EPA's SDWIS records, by city, system, or contaminant. This page covers its hosted endpoint (https://mcp.tapwatermap.com/mcp).

Is the io.github.squidcode/tapwatermap MCP server safe to use?

io.github.squidcode/tapwatermap scores 84 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the io.github.squidcode/tapwatermap MCP server expose?

io.github.squidcode/tapwatermap exposes 10 tools: search, fetch, search_cities, get_city_water, get_water_system, and 5 more. Their descriptions and schemas cost roughly 643 tokens of context every time the server is loaded.

Does the io.github.squidcode/tapwatermap MCP server require authentication?

No. We connected to io.github.squidcode/tapwatermap without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the io.github.squidcode/tapwatermap MCP server still maintained?

io.github.squidcode/tapwatermap is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.