Tapwhich
REMOTE · TAPWHICH.OPENKRILL.APP
Which of your cards to tap at a place: the cashback, cap and conditions, from the banks' own pages.
Available components
Last scanned (12 hours ago)
Scores higher than 63% of remote servers
Reachable. Last reached 17 Oct 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 Security83
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC is configured correctly; the domain's records validate against the full chain to the root. View diagnostics → Pass
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability57
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 548 tokens (~548/item across 1 items; 1 tools + 0 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 Management3
- Stability observed for 1 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
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 1 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 2 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (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.
- 17 Oct 26 +1
- Stability: unverified → 0.03 ▲ functional
- 16 Oct 26 71
First indexed and scored.
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 17 Oct 2026 · Probed https://tapwhich.openkrill.app/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=openkrill.app | CN=WE1,O=Google Trust Services,C=US | 1 Oct 2026 | 30 Dec 2026 | ECDSA 256 | ECDSA-SHA256 | 6cf69bd63092735913f8e43cc0ae532b |
| SANs: openkrill.app, *.openkrill.app | ||||||
| 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 secure
Validation of tapwhich.openkrill.app. — Secure
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| app. | present | 23684 | 8 | Verified |
| openkrill.app. | present | 2371 | 13 | Verified |
| tapwhich.openkrill.app. | Verified address RRset verified with the apex keys |
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 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=31536000; includeSubDomains |
| content-security-policy | default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; style-src 'self'; img-src 'self' data: blob:; connect-src 'self' https://cloudflareinsights.com; font-src 'self'; object-src 'none'; base-uri 'none'; form-action 'self'; frame-ancestors 'none' |
| x-content-type-options | nosniff |
| referrer-policy | no-referrer |
| permissions-policy | camera=(), microphone=(), geolocation=(self), payment=() |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://tapwhich.openkrill.app/mcp | Verified | 200 | |
| http (plaintext) | http://tapwhich.openkrill.app/mcp | HTTPS enforced | 301 | https://tapwhich.openkrill.app/mcp |
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 →
pick_card Which card to tap here ~360
Use this when someone asks which of their credit or debit cards to pay with at a shop, app, category or city, to get the most cashback. Pass the place (a merchant such as Grab or Shopee, a category such as dining or supermarket, or a city such as Tokyo, or both: 'dining in Tokyo') and the cards they hold (names or ids). It answers in one line, 'use card X here, because Y, up to cap Z', with the second-best card, each card's cap and conditions, and the bank source link. The data pack covers Vietnam-issued cards; amounts are in VND.
| Name | Type | Req | Description |
|---|---|---|---|
| amount | number | – | Purchase amount, in VND unless currency says otherwise. Default 1,000,000 VND. |
| cards | array | yes | The cards the person holds, by name ('VPBank Z JCB') or id ('vpbank-z-jcb'). |
| channel | string | – | Online or in a shop, when the place alone does not say. |
| currency | string | – | ISO code of amount when the person gives a foreign amount, such as JPY for 8,000 yen. The tool converts at its own dated rate; do not convert yourself. |
| date | string | – | Purchase date YYYY-MM-DD. Default today in Vietnam. |
| picks | object | – | Bonus categories picked on pick-N cards, by group (vib-one, vib-max, cake-freedom, msb-mdigi). |
| place | string | yes | Merchant, category or city, for example 'Grab', 'supermarket', 'dining in Tokyo'. |
| statement_spend | object | – | Spend so far this statement by card id, for minimum spend and tiers. |
| Name | Type | Req | Description |
|---|---|---|---|
| amount | number | yes | – |
| answer | string | yes | – |
| best | object|null | – | – |
| check | string | yes | – |
| converted_from | object|null | – | – |
| currency | string | yes | – |
| date | string | yes | – |
| freshness | string|null | – | – |
| pack | object | yes | – |
| place | object | yes | – |
| ranking | array | yes | – |
| second | object|null | – | – |
No examples provided.
How do I install the Tapwhich MCP server?
Tapwhich is a hosted endpoint at https://tapwhich.openkrill.app/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 · tapwhich.openkrill.app
claude mcp add --transport http app-openkrill-tapwhich 'https://tapwhich.openkrill.app/mcp'
What is the Tapwhich MCP server?
Tapwhich is an MCP server listed in the public MCP registry as app.openkrill/tapwhich. Which of your cards to tap at a place: the cashback, cap and conditions, from the banks' own pages. This page covers its hosted endpoint (https://tapwhich.openkrill.app/mcp).
Is the Tapwhich MCP server safe to use?
Tapwhich scores 72 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 Tapwhich MCP server expose?
Tapwhich exposes 1 tool: pick_card. Their descriptions and schemas cost roughly 360 tokens of context every time the server is loaded.
Does the Tapwhich MCP server require authentication?
No. We connected to Tapwhich without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Tapwhich MCP server still maintained?
Tapwhich is still listed as active in the MCP registry. We last reached this channel on 17 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.