Cruncher
NPM · @SLBDN/CRUNCHER-MCP · SCANNED SEP 24
Scientific calculator MCP server with 43 tools: arithmetic, trig, stats, unit conversion.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security100
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- No production dependencies, so there is no dependency health to assess. View diagnostics → Pass
Provenance & Transparency48
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 85 days ago).Pass
- Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability68
- AI-judged instruction clarity (good).Pass
- Tool/resource definitions use about 1179 tokens (~34/item across 34 items; 34 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management83
- Stability observed for 25 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage68
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 4% 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 34 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 34 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
How do I install the Cruncher MCP server?
Cruncher runs locally as an npm package, launched with npx -y @slbdn/cruncher-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · @slbdn/cruncher-mcp
claude mcp add islobodan-cruncher-mcp -- npx -y @slbdn/cruncher-mcp
{
"mcpServers": {
"islobodan-cruncher-mcp": {
"command": "npx",
"args": [
"-y",
"@slbdn/cruncher-mcp"
]
}
}
} {
"servers": {
"islobodan-cruncher-mcp": {
"command": "npx",
"args": [
"-y",
"@slbdn/cruncher-mcp"
]
}
}
} codex mcp add islobodan-cruncher-mcp -- npx -y @slbdn/cruncher-mcp
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"islobodan-cruncher-mcp": {
"type": "local",
"command": [
"npx",
"-y",
"@slbdn/cruncher-mcp"
],
"enabled": true
}
}
} openclaw mcp add islobodan-cruncher-mcp --command npx --arg -y --arg @slbdn/cruncher-mcp
mcp_servers:
islobodan-cruncher-mcp:
command: "npx"
args: ["-y", "@slbdn/cruncher-mcp"] {
"McpServers": {
"islobodan-cruncher-mcp": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@slbdn/cruncher-mcp"
]
}
}
} assistant mcp add islobodan-cruncher-mcp -t stdio -c npx -a -y @slbdn/cruncher-mcp
{
"mcpServers": {
"islobodan-cruncher-mcp": {
"command": "npx",
"args": [
"-y",
"@slbdn/cruncher-mcp"
]
}
}
} 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.
- 24 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 80 to 83. That category is still filling its 30-day observation window: 24 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.
- 23 Sept 26 −3
- Stability: pass → 0.80 functional
- 22 Sept 26 0
- Stability: 0.97 → pass security
- 21 Sept 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.
- 19 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.
- 17 Sept 26 −2
- Stability: pass → 0.83 functional
- 16 Sept 26 0
- Stability: 0.97 → pass security
- 15 Sept 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.
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 24 Sept 2026 · Analysed npm/@slbdn/cruncher-mcp@1.2.29
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Dependencies 0 packages
| Packages resolved | 0 |
|---|---|
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
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 →
absolute ~17
Absolute value.
| Name | Type | Req | Description |
|---|---|---|---|
| value | number | yes | – |
No output schema declared.
No examples provided.
acos ~38
Arccosine. Result in degrees by default, or radians with unit param.
| Name | Type | Req | Description |
|---|---|---|---|
| unit | string | – | – |
| value | number | yes | – |
No output schema declared.
No examples provided.
add ~25
Adds two numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| a | number | yes | – |
| b | number | yes | – |
No output schema declared.
No examples provided.
asin ~37
Arcsine. Result in degrees by default, or radians with unit param.
| Name | Type | Req | Description |
|---|---|---|---|
| unit | string | – | – |
| value | number | yes | – |
No output schema declared.
No examples provided.
atan ~37
Arctangent. Result in degrees by default, or radians with unit param.
| Name | Type | Req | Description |
|---|---|---|---|
| unit | string | – | – |
| value | number | yes | – |
No output schema declared.
No examples provided.
avg ~21
Average (mean) of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
convert_unit ~60
Convert between common units. Categories: length, weight, temperature, area, volume, time, speed, digital_storage.
| Name | Type | Req | Description |
|---|---|---|---|
| category | string | yes | – |
| from | string | yes | – |
| to | string | yes | – |
| value | number | yes | – |
No output schema declared.
No examples provided.
cosine ~39
Cosine. Angle in degrees by default, or radians with unit: "radians".
| Name | Type | Req | Description |
|---|---|---|---|
| angle | number | yes | – |
| unit | string | – | – |
No output schema declared.
No examples provided.
count ~17
Count elements.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
divide ~31
Divides two numbers. Errors on zero divisor.
| Name | Type | Req | Description |
|---|---|---|---|
| a | number | yes | – |
| b | number | yes | – |
No output schema declared.
No examples provided.
evaluate_expression ~142
Evaluate a mathematical expression. PRIMARY tool for ALL math: +, -, *, /, %, ^. Functions: sqrt, sin, cos, tan, asin, acos, atan, log10, ln, log(x,base), abs, round, floor, ceil, min, max. Constants: pi, e, tau, phi, sqrt2, euler_mascheroni, c, g, G, h, k, R, NA, e_charge, m_e, m_p. Parentheses and scientific notation (1e6) supported. Use explicit operators: 2 * pi, not 2pi.
| Name | Type | Req | Description |
|---|---|---|---|
| expression | string | yes | – |
No output schema declared.
No examples provided.
factorial ~52
Factorial of non-negative integer (n!). n > 170 overflows.
| Name | Type | Req | Description |
|---|---|---|---|
| n | number | yes | – |
| timeout | number | – | Custom timeout in ms (100-60000, default: 3000) |
No output schema declared.
No examples provided.
get_angle_mode ~15
Get current trig angle mode.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
get_constant ~29
Returns a mathematical, physical, or chemical constant. See enum values.
| Name | Type | Req | Description |
|---|---|---|---|
| name | string | yes | – |
No output schema declared.
No examples provided.
logarithm ~27
Base-10 logarithm. Errors on non-positive input.
| Name | Type | Req | Description |
|---|---|---|---|
| value | number | yes | – |
No output schema declared.
No examples provided.
max ~18
Maximum of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
median ~40
Median of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
| timeout | number | – | Custom timeout in ms (100-60000, default: 3000) |
No output schema declared.
No examples provided.
min ~18
Minimum of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
modulo ~34
Remainder of a / b. Errors on zero divisor.
| Name | Type | Req | Description |
|---|---|---|---|
| a | number | yes | – |
| b | number | yes | – |
No output schema declared.
No examples provided.
multiply ~27
Multiplies two numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| a | number | yes | – |
| b | number | yes | – |
No output schema declared.
No examples provided.
natural_log ~27
Natural logarithm (ln). Errors on non-positive input.
| Name | Type | Req | Description |
|---|---|---|---|
| value | number | yes | – |
No output schema declared.
No examples provided.
percentage_change ~40
Percentage change from A to B. e.g., 50→80 = +60%
| Name | Type | Req | Description |
|---|---|---|---|
| from | number | yes | – |
| to | number | yes | – |
No output schema declared.
No examples provided.
percentage_of ~42
What is X% of Y? e.g., 15% of 200 = 30
| Name | Type | Req | Description |
|---|---|---|---|
| percent | number | yes | – |
| total | number | yes | – |
No output schema declared.
No examples provided.
percentage_reverse ~42
X is Y% of what? e.g., 30 is 15% of 200
| Name | Type | Req | Description |
|---|---|---|---|
| percent | number | yes | – |
| value | number | yes | – |
No output schema declared.
No examples provided.
power ~29
Raises a to the power of b.
| Name | Type | Req | Description |
|---|---|---|---|
| base | number | yes | – |
| exponent | number | yes | – |
No output schema declared.
No examples provided.
range ~23
Range (max - min) of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
set_angle_mode ~30
Set global trig angle mode. Individual calls with unit param override this.
| Name | Type | Req | Description |
|---|---|---|---|
| mode | string | yes | – |
No output schema declared.
No examples provided.
sine ~39
Sine. Angle in degrees by default, or radians with unit: "radians".
| Name | Type | Req | Description |
|---|---|---|---|
| angle | number | yes | – |
| unit | string | – | – |
No output schema declared.
No examples provided.
sqrt ~22
Square root. Errors on negative input.
| Name | Type | Req | Description |
|---|---|---|---|
| value | number | yes | – |
No output schema declared.
No examples provided.
std_dev ~39
Sample standard deviation (n-1). Set population: true for population (n).
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
| population | boolean | – | – |
No output schema declared.
No examples provided.
subtract ~27
Subtracts two numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| a | number | yes | – |
| b | number | yes | – |
No output schema declared.
No examples provided.
sum ~18
Sum of numbers.
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
No output schema declared.
No examples provided.
tangent ~39
Tangent. Angle in degrees by default, or radians with unit: "radians".
| Name | Type | Req | Description |
|---|---|---|---|
| angle | number | yes | – |
| unit | string | – | – |
No output schema declared.
No examples provided.
variance ~38
Sample variance (n-1). Set population: true for population variance (n).
| Name | Type | Req | Description |
|---|---|---|---|
| numbers | array | yes | – |
| population | boolean | – | – |
No output schema declared.
No examples provided.
What is the Cruncher MCP server?
Cruncher is an MCP server listed in the public MCP registry as io.github.islobodan/cruncher-mcp. Scientific calculator MCP server with 43 tools: arithmetic, trig, stats, unit conversion. This page covers its npm package (@slbdn/cruncher-mcp).
Is the Cruncher MCP server safe to use?
Cruncher scores 79 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 24 September 2026. It declares no install or post-install scripts. 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 Cruncher MCP server expose?
Cruncher exposes 34 tools: add, subtract, multiply, divide, power, and 29 more. Their descriptions and schemas cost roughly 1,179 tokens of context every time the server is loaded.
Is the Cruncher MCP server still maintained?
Cruncher is still listed as active in the MCP registry. We last reached this channel on 24 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What licence is the Cruncher MCP server under?
Cruncher declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.