Independent signed math checks for AI agents: PASS or FAIL plus a link anyone can open. Free beta.
Maintain this server? Claim it
Call this server's tools from your browser. Nothing to install.
Free beta key, sent as Bearer cb_test_... Get one at https://checkbooth.dev/kiosk/key
Requests go through mcptry because browsers can't call most MCP servers directly. Header values are sent to the server for that request only and are never stored or logged.
Tool list from our last check. Connect live to refresh it.
Paste text (up to 8,000 characters). We find every inline "arithmetic = number" claim and recompute it at the stated digits. Signed receipt. We keep only hashes of your text.
Pick your client. Values in capitals, like YOUR_TOKEN, are yours to fill in.
Run in a terminal
claude mcp add --transport http checkbooth https://checkbooth.dev/mcp
Headers
Authorization (optional, not in the config above): Free beta key, sent as Bearer cb_test_... Get one at https://checkbooth.dev/kiosk/keyTool list last changed Nov 9, 2026.
Paste text (up to 8,000 characters). We find every inline "arithmetic = number" claim and recompute it at the stated digits. Signed receipt. We keep only hashes of your text.
| Argument | Type | Description |
|---|---|---|
| text* | string |
{
"type": "object",
"required": [
"text"
],
"properties": {
"text": {
"type": "string",
"maxLength": 8000
}
}
}List the whole Checkbooth tool chest with honest status tags (BUILT, COMING, ON REQUEST). Filter by words, family or status. Free.
| Argument | Type | Description |
|---|---|---|
| query | string | |
| family | string | |
| status | string | |
| include_staged | boolean | Default false: only tools you can call right now. |
{
"type": "object",
"properties": {
"query": {
"type": "string",
"maxLength": 80
},
"family": {
"type": "string"
},
"status": {
"type": "string"
},
"include_staged": {
"type": "boolean",
"description": "Default false: only tools you can call right now."
}
},
"additionalProperties": false
}Get a free capped beta key (cb_test_...). Shown once; we keep only its hash.
No arguments.
{
"type": "object",
"properties": {}
}Exact credit price of any capability before you spend anything. Free.
| Argument | Type | Description |
|---|---|---|
| capability* | string |
{
"type": "object",
"required": [
"capability"
],
"properties": {
"capability": {
"type": "string"
}
}
}Vote for a COMING capability, or describe one we do not list. Free; helps decide what opens next.
| Argument | Type | Description |
|---|---|---|
| use_case | string | |
| capability* | string |
{
"type": "object",
"required": [
"capability"
],
"properties": {
"use_case": {
"type": "string",
"maxLength": 280
},
"capability": {
"type": "string"
}
}
}Run up to 8 checks or formulas in one call and get ONE signed bundle receipt. Each step is either a verify_math_or_tolerance argument object or {formula, inputs}. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
| Argument | Type | Description |
|---|---|---|
| steps* | array |
{
"type": "object",
"required": [
"steps"
],
"properties": {
"steps": {
"type": "array",
"maxItems": 8
}
}
}Run one of our built-in physics formulas (sound speed, echo range, drop shock, field magnitude, thermal, timing and more) on YOUR inputs. Find formula codes and their input names with discover_capabilities. Every formula reproduces its own reference example before it is listed. Each result carries its limits. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
| Argument | Type | Description |
|---|---|---|
| inputs* | object | |
| formula* | string |
{
"type": "object",
"required": [
"formula",
"inputs"
],
"properties": {
"inputs": {
"type": "object"
},
"formula": {
"type": "string",
"pattern": "^f[a-z2-9]{5}$"
}
}
}Verify 2 to 20 of your Checkbooth receipts and seal them into ONE signed design-review bundle with a single /check link.
| Argument | Type | Description |
|---|---|---|
| tokens* | array | |
| review_title | string |
{
"type": "object",
"required": [
"tokens"
],
"properties": {
"tokens": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 20,
"minItems": 2
},
"review_title": {
"type": "string",
"maxLength": 120
}
}
}Paste a README, PR description, spec or memo plus the Checkbooth results it relies on. We check every number in the text against those signed results and flag overclaim phrases (for example "verified across all conditions", "guaranteed", "certified"). Deterministic, no AI. Signed receipt.
| Argument | Type | Description |
|---|---|---|
| text* | string | |
| results* | array | Full Checkbooth results exactly as returned (each carries its receiptToken). |
{
"type": "object",
"required": [
"text",
"results"
],
"properties": {
"text": {
"type": "string",
"maxLength": 8000
},
"results": {
"type": "array",
"maxItems": 10,
"description": "Full Checkbooth results exactly as returned (each carries its receiptToken)."
}
}
}Independent, signed recompute of your numbers: formula, worst-case tolerance stack, power budget, Nyquist sampling, or rated range. Returns PASS/FAIL/INVALID and a receipt a second party can check at /check. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
| Argument | Type | Description |
|---|---|---|
| check* | any |
{
"type": "object",
"required": [
"check"
],
"properties": {
"check": {
"enum": [
"expression",
"tolerance_stack",
"power_budget",
"nyquist",
"range"
]
}
}
}Check that a Checkbooth receipt is genuine and unchanged. Free, no key needed.
| Argument | Type | Description |
|---|---|---|
| token* | string |
{
"type": "object",
"required": [
"token"
],
"properties": {
"token": {
"type": "string"
}
}
}Recompute a formula that uses trig (sin, cos, tan, asin, acos, atan; degree forms sind, cosd, tand, asind, acosd, atand) and compare it to a target. Signed receipt. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
| Argument | Type | Description |
|---|---|---|
| expect* | object | |
| values | object | |
| expression* | string |
{
"type": "object",
"required": [
"expression",
"expect"
],
"properties": {
"expect": {
"type": "object"
},
"values": {
"type": "object"
},
"expression": {
"type": "string",
"maxLength": 300
}
}
}We read every tool's name, description and inputs the way the model will, looking for instructions hidden from you. A clean result means no warning signs, not a guarantee. Scanned Nov 9, 2026.
Takes a password, API key or token as an argument, so the secret passes through the model's context and chat logs.
Fix: Read credentials from the server's own configuration (environment, OAuth) instead of a tool argument.
What changed in this server's tools since we started watching, newest first. Each change is scanned again.
Run up to 8 checks or slice tools in one call and get ONE signed bundle receipt. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
Run one of our tested house math slices (sound speed, echo range, drop shock, field magnitude and more) on YOUR inputs. Only slices whose worked examples reproduce exactly are callable. Each result carries the slice's own limits. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
Get a free capped beta key (bb_test_...).(cb_test_...). Shown once; we keep only its hash.
Run up to 8 checks or formulas in one call and get ONE signed bundle receipt. Each step is either a verify_math_or_tolerance argument object or {formula, inputs}. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
Run one of our built-in physics formulas (sound speed, echo range, drop shock, field magnitude, thermal, timing and more) on YOUR inputs. Find formula codes and their input names with discover_capabilities. Every formula reproduces its own reference example before it is listed. Each result carries its limits. Planning and math verification check only — not a licensed professional engineering review, stamp, or sign-off.
List the whole Checkbooth tool chest with honest status tags (BUILT, COMING, ON REQUEST). Filter by words, drawerfamily or status. Free.
{
"type": "object",
"properties": {
"query": {
"type": "string",
"maxLength": 80
},
"drawer": {
"type": "string"
},
"status": {
"type": "string"
},
"include_staged": {
"type": "boolean",
"description": "Default false: only tools you can call right now."
}
},
"additionalProperties": false
}{
"type": "object",
"properties": {
"query": {
"type": "string",
"maxLength": 80
},
"family": {
"type": "string"
},
"status": {
"type": "string"
},
"include_staged": {
"type": "boolean",
"description": "Default false: only tools you can call right now."
}
},
"additionalProperties": false
}