501c3.HELP nonprofit compliance
REMOTE · MCP.501C3.HELP
Nonprofit compliance rules for all 50 US states, each with its official citation and status
Available components
Last scanned (17 hours ago)
Scores higher than 60% of remote servers
Reachable. Last reached 4 Nov 2026.
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 Security46
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not fully verified: no authorisation is required to call this server, and 3 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe. See how to fix → View diagnostics → Unverified
- HTTPS enforcement could not be verified: the plaintext port answered with HTTP 405, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability83
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 389 tokens (~129/item across 3 items; 3 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management97
- Stability observed for 29 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 3 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 4 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
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.
- 4 Nov 26 −1
- Stability: pass → 0.97 functional
- 31 Oct 26 +1
- Stability: 0.97 → pass security
- 29 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
- 27 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 24 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 73 to 77. That category is still filling its 30-day observation window: 22 days of observed history at the previous scan, 23 at this one. The score rises as the window fills, whether or not the server changes.
- 22 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 67 to 70. That category is still filling its 30-day observation window: 20 days of observed history at the previous scan, 21 at this one. The score rises as the window fills, whether or not the server changes.
- 20 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 60 to 63. That category is still filling its 30-day observation window: 18 days of observed history at the previous scan, 19 at this one. The score rises as the window fills, whether or not the server changes.
- 18 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 53 to 57. That category is still filling its 30-day observation window: 16 days of observed history at the previous scan, 17 at this one. The score rises as the window fills, whether or not the server changes.
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 4 Nov 2026 · Probed https://mcp.501c3.help/
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=501c3.help | CN=WE1,O=Google Trust Services,C=US | 1 Oct 2026 | 30 Dec 2026 | ECDSA 256 | ECDSA-SHA256 | a61ff5d815b2397d0efa4a3854ddd61f |
| SANs: 501c3.help, mcp.501c3.help, *.mcp.501c3.help | ||||||
| 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.501c3.help. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| help. | present | 10505, 58472 | 13, 13 | Verified |
| 501c3.help. | 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.501c3.help/ | Verified | 200 | |
| http (plaintext) | http://mcp.501c3.help/ | Inconclusive | 405 |
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 →
compare_states ~116
The same compliance topic across several US states, for deciding where to incorporate or for an organization that operates in more than one state. Each state's records carry their own citation and verification status; a record marked review_required is unsettled and must not be presented as a settled rule. Accepts up to eight states.
| Name | Type | Req | Description |
|---|---|---|---|
| states | array | yes | State names or two-letter abbreviations. Up to eight. |
| topic | string | yes | The topic to compare, for example 'solicitation', 'reporting', 'formation', 'tax'. |
No output schema declared.
No examples provided.
get_filing_deadlines ~85
Every requirement in one US state that has a filing deadline attached, with the deadline in plain words, the form or portal, the fee, and the official citation. Use this for 'what is due and when'. Deadlines on records marked review_required are not settled and must be shown as unconfirmed.
| Name | Type | Req | Description |
|---|---|---|---|
| state | string | yes | State name or two-letter abbreviation. |
No output schema declared.
No examples provided.
get_state_requirements ~141
Nonprofit compliance requirements for one US state, from 501c3.help's sourced records: formation, governance, charitable solicitation registration, reporting, tax and employment. Every record carries its official citation and a verification status. Records marked review_required are unsettled and must be presented as such, never as a settled rule. Optionally narrow by topic. Returns a limited number of records, not the whole state.
| Name | Type | Req | Description |
|---|---|---|---|
| state | string | yes | State name or two-letter abbreviation, for example 'Kansas' or 'KS'. |
| topic | string | – | Optional topic filter, matched loosely, for example 'solicitation', 'reporting', 'tax'. |
No output schema declared.
No examples provided.
How do I install the 501c3.HELP nonprofit compliance MCP server?
501c3.HELP nonprofit compliance is a hosted endpoint at https://mcp.501c3.help/, 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.501c3.help
claude mcp add --transport http help-501c3-compliance 'https://mcp.501c3.help/'
What is the 501c3.HELP nonprofit compliance MCP server?
501c3.HELP nonprofit compliance is an MCP server listed in the public MCP registry as help.501c3/compliance. Nonprofit compliance rules for all 50 US states, each with its official citation and status. This page covers its hosted endpoint (https://mcp.501c3.help/).
Is the 501c3.HELP nonprofit compliance MCP server safe to use?
501c3.HELP nonprofit compliance scores 73 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 501c3.HELP nonprofit compliance MCP server expose?
501c3.HELP nonprofit compliance exposes 3 tools: get_state_requirements, compare_states, get_filing_deadlines. Their descriptions and schemas cost roughly 342 tokens of context every time the server is loaded.
Does the 501c3.HELP nonprofit compliance MCP server require authentication?
No. We connected to 501c3.HELP nonprofit compliance without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the 501c3.HELP nonprofit compliance MCP server still maintained?
501c3.HELP nonprofit compliance is still listed as active in the MCP registry. We last reached this channel on 4 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.