McpStamp Dunning Letters
REMOTE · MCP.ZOVO.ONE · 2 COMPONENTS
Chase unpaid invoices: reminder, firm reminder and final notice letters, and a daily chase list.
Available components
Last scanned (21 hours ago)
Scores higher than 99% of remote servers
Reachable. Last reached 4 Nov 2026.
Category Finance and Payments
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 Security94
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation is enforced on tool calls, advertised via RFC 9728 protected-resource metadata. Discovery is public, which costs nothing: no tool can be invoked without a token. View diagnostics → Pass
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
- The authorisation server offers only Dynamic Client Registration (RFC 7591), which MCP 2026-07-28 deprecated in favour of Client ID Metadata Documents. View diagnostics → Partial
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability86
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 1558 tokens (~119/item across 13 items; 11 tools + 2 resources), over budget; trim descriptions and params. See how to fix → Fail
- 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 Coverage99
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 97% 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
- All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.Pass
- An AI judge read all 13 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
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.
- 2 Nov 26 0
- The server rewrote its instructions, which are the text every model session reads security
- 24 Oct 26 +2
- HSTS header: unverified → pass ▲ security
- 23 Oct 26 −2
- HSTS header: pass → unverified ▼ security
- 16 Oct 26 0
- Server version: 0.22.0 → 0.22.6 functional
- 12 Oct 26 +70
- Transport: unverified → pass ▲ security
- Injection markers: unverified → pass ▲ security
- Authorization: unverified → pass ▲ security
- Stability: unverified → pass ▲ security
- Endpoint reachability: behind authorisation → reachable ▲ functional
- MCP protocol: unverified → pass ▲ functional
- Schema quality: unverified → 100 ▲ functional
- Tool coverage: unverified → 100 ▲ functional
- 10 Oct 26 −68
- Endpoint reachability: reachable → behind authorisation ▼ security
- Transport: pass → unverified ▼ security
- Stability: 0.83 → unverified ▼ security
- Authorization: pass → unverified ▼ security
- Tool safety: pass → unverified ▼ security
- Capabilities: pass → unverified ▼ functional
- Schema quality: 100 → unverified ▼ functional
- Tool coverage: 100 → unverified ▼ functional
- 7 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 73 to 83. That category is still filling its 30-day observation window: 22 days of observed history at the previous scan, 25 at this one. The score rises as the window fills, whether or not the server changes.
- 4 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 70 to 73. That category is still filling its 30-day observation window: 21 days of observed history at the previous scan, 22 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.zovo.one/mcp/dunning-letters
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=zovo.one | CN=WE1,O=Google Trust Services,C=US | 31 Oct 2026 | 29 Jan 2027 | ECDSA 256 | ECDSA-SHA256 | 39e1adfa4eb6500e0e3d48868766e3e9 |
| SANs: zovo.one, mcp.zovo.one, *.mcp.zovo.one | ||||||
| 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.zovo.one. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| one. | present | 64939 | 8 | Verified |
| zovo.one. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication Enforced and verified
The endpoint asked for a token and published valid RFC 9728 metadata describing how to get one.
| Result | Enforced and verified |
|---|---|
| Enforced | On tool calls |
| HTTP status | 200 |
WWW-Authenticate challenge Bearer realm="mcp.zovo.one", resource_metadata="https://mcp.zovo.one/.well-known/oauth-protected-resource/mcp/dunning-letters"
Bearer realm="mcp.zovo.one", resource_metadata="https://mcp.zovo.one/.well-known/oauth-protected-resource/mcp/dunning-letters"| Header | Value |
|---|---|
| strict-transport-security | max-age=15552000; includeSubDomains; preload |
| x-content-type-options | nosniff |
Protected resource metadata
| Document | https://mcp.zovo.one/.well-known/oauth-protected-resource/mcp/dunning-letters |
|---|---|
| Retrieved | Yes |
| Resource | https://mcp.zovo.one/mcp/dunning-letters |
| Authorisation server | https://mcp.zovo.one |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://mcp.zovo.one/mcp/dunning-letters | Verified | 200 | |
| http (plaintext) | http://mcp.zovo.one/mcp/dunning-letters | HTTPS enforced | 301 | https://mcp.zovo.one/mcp/dunning-letters |
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 →
aging_summary Aging summary of what is owed ~87
The aging summary across every unpaid invoice: current, 1-30, 31-60, 61-90 and 91+ day buckets, with counts and totals in integer cents, per currency. This is the answer to "how much am I owed, and how stale is it".
| Name | Type | Req | Description |
|---|---|---|---|
| on | string | – | The date to age against, YYYY-MM-DD. Default today |
No output schema declared.
No examples provided.
chase_today What to chase today ~111
The day's chase list: which invoices cross an escalation threshold today, which letter to send each and how long it has been waiting, what falls due in the next few days, and which invoices have had all three letters and need a decision outside this server.
| Name | Type | Req | Description |
|---|---|---|---|
| on | string | – | The date to run the list for, YYYY-MM-DD, e.g. to see what Monday will need. Default today |
| within_days | integer | – | How far ahead to list letters coming due, default 7 days |
No output schema declared.
No examples provided.
invoice_delete Delete an invoice from the register ~79
Delete an invoice entered wrongly, by id or reference: the record, its payments and its letter history. The id is not reissued, so a gap in the DUN series is the record that a deletion happened.
| Name | Type | Req | Description |
|---|---|---|---|
| invoice | string | yes | The chased invoice: its id (DUN-2026-0001) or its invoice reference |
No output schema declared.
No examples provided.
invoice_register Register an unpaid invoice to chase ~313
Start chasing an unpaid invoice: register the client, the invoice reference, the amount in integer cents, the currency and the due date, and get the three-letter escalation schedule (reminder 1, reminder 2, final notice) with the date each falls due. Free tier: 3 unpaid invoices chased at once.
| Name | Type | Req | Description |
|---|---|---|---|
| amount_minor | integer | yes | The invoice amount in whole minor units (integer cents). 125000 is USD 1,250.00 |
| client | string | yes | Who owes the money, e.g. Acme Ltd |
| currency | string | yes | ISO code the invoice was issued in |
| due | string | yes | The date payment fell due, YYYY-MM-DD. The ladder is anchored to this date |
| duplicate_ok | boolean | – | Register even though an identical invoice is already on the register. Default false |
| gaps | array | – | Days after the due date at which reminder 1, reminder 2 and the final notice fall due, strictly increasing. Default [7, 14, 21] |
| issued | string | – | The date the invoice was issued, YYYY-MM-DD, for the letter's reference line |
| late_fee_percent_per_month | number | – | Late payment interest your terms allow, percent per month, simple and pro-rata. When set, reminder 2 and the final notice state the accrued figure |
| note | string | – | – |
| reference | string | yes | The invoice number being chased, e.g. INV-1042 |
No output schema declared.
No examples provided.
invoice_status The full state of one chased invoice ~99
One chased invoice in full: what was billed, what has been paid and what is still owed, every letter sent with its date, the escalation schedule with each stage's state, and what happens next and when.
| Name | Type | Req | Description |
|---|---|---|---|
| invoice | string | yes | The chased invoice: its id (DUN-2026-0001) or its invoice reference |
| on | string | – | The date to judge lateness against, YYYY-MM-DD. Default today |
No output schema declared.
No examples provided.
letter_render Generate the chase letter for the current stage ~209
Chase an unpaid invoice: generate the letter for the current stage of the ladder -- reminder 1 (polite), reminder 2 (firm, with the late fees note) or the final notice (before-action wording) -- as Markdown or as self-contained printable HTML. Nothing is emailed or sent anywhere: this server produces the letter text, and sending it is your act. Record the sending with letter_sent so the ladder advances.
| Name | Type | Req | Description |
|---|---|---|---|
| format | string | – | markdown (default) or html: a self-contained printable page with no external anything |
| invoice | string | yes | The chased invoice: its id (DUN-2026-0001) or its invoice reference |
| on | string | – | The letter's date, YYYY-MM-DD; late fees accrue to it and the final-notice deadline is 7 days after it. Default today |
| stage | number | – | Render a specific stage instead of the one currently due, to preview or to re-issue a letter already sent |
No output schema declared.
No examples provided.
letter_sent Record that a letter was sent ~119
Record that a chase letter was actually sent, with its date, so the ladder advances to the next stage. Letters go out in order: reminder 2 cannot be recorded before reminder 1. Returns what is due next and when.
| Name | Type | Req | Description |
|---|---|---|---|
| invoice | string | yes | The chased invoice: its id (DUN-2026-0001) or its invoice reference |
| sent | string | – | The date it was sent, YYYY-MM-DD. Default today |
| stage | number | – | Which letter went out. Default the lowest unsent stage |
No output schema declared.
No examples provided.
license_activate Activate license ~76
Turn Pro on for this connection with key, an MCPL1.<payload>.<signature> issued at checkout for this server or the bundle. Data under your token stays; a wrong or expired key changes nothing. license_status confirms it.
| Name | Type | Req | Description |
|---|---|---|---|
| key | string | yes | License key from checkout, MCPL1.<payload>.<signature> |
No output schema declared.
No examples provided.
license_status License status ~55
Report this endpoint's licence state for your token as JSON: the product, the tier free or pro, why it is not Pro, and the checkout URL. Call it to explain a free-tier refusal. No arguments, nothing changes.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
overdue_list List overdue invoices ~85
Every unpaid invoice past its due date: how many days late, what is still owed, which letters have gone out, and what is due next and when. Sorted by days late, worst first.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Maximum rows, default and ceiling 2000 |
| on | string | – | The date to judge lateness against, YYYY-MM-DD. Default today |
No output schema declared.
No examples provided.
payment_record Record a payment received ~137
Record money received against a chased invoice, in whole MINOR units: a part payment lowers what is still chased, a payment that covers the balance closes the ladder and frees the free-tier slot. Returns the outstanding amount.
| Name | Type | Req | Description |
|---|---|---|---|
| amount_minor | integer | yes | What was received, in whole minor units |
| date | string | – | The date the money arrived, YYYY-MM-DD. Default today |
| invoice | string | yes | The chased invoice: its id (DUN-2026-0001) or its invoice reference |
| note | string | – | How it was paid, e.g. Bank transfer, or what it was against |
No output schema declared.
No examples provided.
How do I install the McpStamp Dunning Letters MCP server?
McpStamp Dunning Letters is a hosted endpoint at https://mcp.zovo.one/mcp/dunning-letters, 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.zovo.one
claude mcp add --transport http theluckystrike-dunning-letters 'https://mcp.zovo.one/mcp/dunning-letters'
What is the McpStamp Dunning Letters MCP server?
McpStamp Dunning Letters is an MCP server listed in the public MCP registry as io.github.theluckystrike/dunning-letters. Chase unpaid invoices: reminder, firm reminder and final notice letters, and a daily chase list. This page covers its hosted endpoint (https://mcp.zovo.one/mcp/dunning-letters).
Is the McpStamp Dunning Letters MCP server safe to use?
McpStamp Dunning Letters scores 95 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 McpStamp Dunning Letters MCP server expose?
McpStamp Dunning Letters exposes 11 tools: invoice_register, payment_record, letter_render, letter_sent, overdue_list, and 6 more. Their descriptions and schemas cost roughly 1,370 tokens of context every time the server is loaded.
Does the McpStamp Dunning Letters MCP server require authentication?
Yes. McpStamp Dunning Letters asked us for credentials when we connected, so you will need to authorise it in your MCP client before it can do anything.
Is the McpStamp Dunning Letters MCP server still maintained?
McpStamp Dunning Letters 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.