Occam
REMOTE · OCCAM.FIT · SCANNED SEP 20
Finds the simplest equation consistent with your data. SINDy and PySR symbolic regression via MCP.
Available components
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 Security80
- 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 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 Usability73
- 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 3860 tokens (~482/item across 8 items; 4 tools + 4 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 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 4 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 6 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 Occam MCP server?
Occam is a hosted endpoint at https://occam.fit/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 · occam.fit
claude mcp add --transport http fit-occam-occam 'https://occam.fit/mcp/'
{
"mcpServers": {
"fit-occam-occam": {
"url": "https://occam.fit/mcp/"
}
}
} {
"servers": {
"fit-occam-occam": {
"type": "http",
"url": "https://occam.fit/mcp/"
}
}
} [mcp_servers.fit-occam-occam] url = "https://occam.fit/mcp/"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"fit-occam-occam": {
"type": "remote",
"url": "https://occam.fit/mcp/",
"enabled": true
}
}
} openclaw mcp add fit-occam-occam --url 'https://occam.fit/mcp/' --transport streamable-http
mcp_servers:
fit-occam-occam:
url: "https://occam.fit/mcp/" {
"McpServers": {
"fit-occam-occam": {
"Transport": "http",
"Url": "https://occam.fit/mcp/"
}
}
} assistant mcp add fit-occam-occam -t streamable-http -u 'https://occam.fit/mcp/'
{
"mcpServers": {
"fit-occam-occam": {
"type": "http",
"url": "https://occam.fit/mcp/"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
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.
- 26 Aug 26 +1
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 25 Aug 26 0
- Stability: 0.97 → pass security
- 24 Aug 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.
- 11 Aug 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 7 Aug 26 0
- The server no longer declares the “experimental” capability functional
- 31 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 30 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 27 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
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 20 Sept 2026 · Probed https://occam.fit/mcp/
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=occam.fit | CN=YE2,O=Let's Encrypt,C=US | 30 Jul 2026 | 28 Oct 2026 | ECDSA 256 | ECDSA-SHA384 | 69191f4c535931ec385d56c1c494e436e59 |
| SANs: occam.fit | ||||||
| CN=YE2,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 4df3b15dd6c0784c507cd37b58e6f115 |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of occam.fit. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| fit. | present | 61939 | 8 | Verified |
| occam.fit. | 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 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000; includeSubDomains |
| content-security-policy | default-src 'none'; style-src 'unsafe-inline'; script-src 'self'; connect-src 'self'; img-src 'self' |
| x-content-type-options | nosniff |
| x-frame-options | DENY |
| referrer-policy | no-referrer |
| permissions-policy | camera=(), microphone=(), geolocation=() |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://occam.fit/mcp/ | Verified | 200 | |
| http (plaintext) | http://occam.fit/mcp/ | HTTPS enforced | 308 | https://occam.fit/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 →
feature_request ~139
Request a feature that Occam doesn't support yet. Use this when you need a capability that Occam doesn't currently offer. Requests are logged and used to prioritize development. Rate limit: 5 requests/hour per IP, 50/hour global — stricter than the compute tools' 10/hour to prevent log flooding. Descriptions longer than 500 characters are truncated.
| Name | Type | Req | Description |
|---|---|---|---|
| description | string | yes | A short description of the feature you need. Examples: 'LaTeX output for equations', 'support for ODE constraints', 'GPU-accelerated search', 'larger dataset limits'. Helps prioritize development. |
| Name | Type | Req | Description |
|---|---|---|---|
| description | string | yes | – |
| message | string | yes | – |
| ok | boolean | yes | – |
No examples provided.
pysr_run ~1,457
Evolutionary Symbolic Regression (PySR). Discovers algebraic equations y = f(x1, x2, ...) from feature/target data. Returns a Pareto front ranked by the complexity/accuracy tradeoff. Slower than SINDy (10-60s); searches often terminate early on convergence. For differential equations from time series, use sindy_run instead. Pricing: free tier up to 100 rows × 8 features, 60s timeout. Beyond that, $0.25 + $0.03 per 100 extra rows + $0.01 per extra feature squared, timeout up to 300s (5 min), via x402 (USDC on Base) or MPP/Stripe. MPP/Stripe adds a flat $0.35 per-transaction fee (Stripe processing), so the MPP challenge amount in a `payment_required` response is $0.35 higher than the x402 amount for the same base price; x402 gets the lower rate. Omit `payment` for free-tier requests; paid requests without a valid credential receive a `payment_required` result with pricing and accepted schemes. Full pricing: occam://pricing Advisory limits: jobs over 50,000 rows or 20 features are accepted but may not converge; response carries a top-level `warning`. Operators: fixed supported set only — custom operators (e.g. 'inv(x) = 1/x') are rejected. Unary: sin, cos, tan, exp, log, log2, log10, sqrt, abs, sinh, cosh, tanh. Binary: +, -, *, /, ^. See also prompt `supported_operators`. Loss metric: `loss` (in `pareto_front[].loss` and `best_loss`) is mean squared error between model prediction and `y` on the full training set — not RMSE, and not normalized by Var(y). A threshold appropriate for one dataset scales with y's magnitude, so set `loss_threshold` with that in mind (e.g. for y values near 1.0, 1e-6 is a tight fit; for y near 1000, the equivalent is 1.0). Early termination: set `loss_threshold` to stop at your noise floor. The server also stops when the search stalls (<1% improvement in the last third of the budget); disable with `stall_detection=fa…
| Name | Type | Req | Description |
|---|---|---|---|
| X | array | yes | 2D array of input features. Each row is an observation, each column is a feature. Free tier: 100 rows, 8 features. Paid tier: up to 50,000 rows, 20 features. |
| binary_operators | – | – | Allowed binary operators, drawn from the fixed supported set: +, -, *, /, ^. Custom operators are NOT supported. Default: +, -, *, /. Pass [] for none. |
| feature_names | – | – | Names for each variable/feature column. Defaults to x0, x1, ... |
| loss_threshold | – | – | Optional early-stop threshold on the best loss found. If set, the search terminates as soon as any Pareto-front member reaches a loss at or below this value, even if the timeout has not been reached.… |
| max_complexity | integer | – | Maximum expression tree size. Higher allows more complex expressions. Default 20, max 25. |
| payment | – | – | Payment credential. Accepts either a JSON object or a JSON-encoded string (FastMCP's transport pre-parses strings whose field annotation is non-bare-`str` into objects, so the object form is canonica… |
| populations | integer | – | Number of evolutionary populations for the search. Default 15, max 20. |
| stall_detection | boolean | – | When true (default), the server stops the search early if the best loss has not improved by more than 1% during the last third of the time budget. This reclaims compute once the search has converged.… |
| timeout_seconds | integer | – | Wall clock time limit in seconds. Free tier: max 60. Paid tier: max 300 (5 minutes). Default 60. |
| unary_operators | – | – | Allowed unary operators, drawn from the fixed supported set: sin, cos, tan, exp, log, log2, log10, sqrt, abs, sinh, cosh, tanh. Custom operators (e.g. 'inv(x) = 1/x') are NOT supported — only the nam… |
| y | array | yes | Target values, one per row of X. |
| Name | Type | Req | Description |
|---|---|---|---|
| best_complexity | – | – | – |
| best_expression | – | – | – |
| best_expression_latex | – | – | – |
| best_loss | – | – | – |
| elapsed_seconds | – | – | – |
| pareto_front | – | – | – |
| queue_seconds | – | – | – |
| stop_reason | – | – | – |
| warning | – | – | – |
No examples provided.
pysr_uncertainty ~858
Bootstrap confidence intervals for the numeric constants of a frozen expression, plus optional prediction bands on an x-grid. Typical flow: call pysr_run, pick an expression from the response (best_expression or a pareto_front entry), pass it back here with the same dataset to get CIs on its fit constants. Returns frequentist bootstrap confidence intervals, not Bayesian credible intervals — posterior inference over expression structures is an open research problem. This tool freezes the expression chosen by the caller and bootstraps only its numeric constants; uncertainty about *which* expression is correct is not quantified. Bootstrap semantics: - If y_sigma is supplied, uses parametric bootstrap (y_b = y + Normal(0, y_sigma)). CI reflects user-stated measurement noise. - Otherwise uses residual bootstrap: fit once, resample residuals. CI reflects estimated-from-residuals noise. Only Float constants in the expression become free parameters. Integers stay structural (the 2 in x**2 is a function-class choice, not a fit constant). Expressions with no Float constants (e.g. "x + y") will be rejected with a validation error. Expression grammar: the `expression` string is parsed by sympy. Accepted operators are the same set pysr_run emits: unary `sin`, `cos`, `tan`, `exp`, `log`, `log2`, `log10`, `sqrt`, `abs`, `sinh`, `cosh`, `tanh`; binary `+`, `-`, `*`, `/`, `^` (or `**`). Whitespace and parenthesization are free. Every free symbol in the expression must correspond to an entry in `feature_names` — an unrecognised symbol is silently treated as a fresh sympy Symbol and the fit will fail downstream rather than reject early. Parse failures (syntax errors, malformed operators) surface as tool errors. If `feature_names` is supplied, its length must equal the number of columns in `X`; a mismatch is rejected with a validation error.…
| Name | Type | Req | Description |
|---|---|---|---|
| X | array | yes | 2D array of input features. Each row is an observation, each column is a feature. Free tier: 100 rows, 8 features. Paid tier: up to 50,000 rows, 20 features. |
| alpha | number | – | Significance level. 0.05 → 95%% CI. Default 0.05. |
| expression | string | yes | The expression to bootstrap, as returned by pysr_run (`best_expression` or a `pareto_front[i].expression`). Only numeric Float constants are treated as free parameters — integers in the expression (e… |
| feature_names | – | – | Names for each variable/feature column. Defaults to x0, x1, ... |
| n_resamples | integer | – | Number of bootstrap resamples. Higher = tighter CIs, more compute. Default 100. |
| x_grid | – | – | Optional 2D grid of feature values at which to report a prediction band. Must have the same number of columns as X. Omit to skip prediction-band computation. |
| y | array | yes | Target values, one per row of X. |
| y_sigma | – | – | Optional per-point measurement standard deviations, or a single scalar applied to all points. When supplied, the helper uses parametric bootstrap (y_b = y + Normal(0, y_sigma)); otherwise it uses res… |
| Name | Type | Req | Description |
|---|---|---|---|
| alpha | number | yes | – |
| bootstrap_method | string | yes | – |
| coefficients | array | yes | – |
| n_requested_resamples | integer | yes | – |
| n_successful_resamples | integer | yes | – |
| note | string | yes | – |
| prediction_ci | – | – | – |
No examples provided.
sindy_run ~889
Sparse Identification of Nonlinear Dynamics (SINDy). Recovers governing differential equations (dx/dt = f(x)) from time series data. Returns human-readable sparse expressions. Fast (seconds). For algebraic y = f(x) relationships without time structure, use pysr_run instead. Pricing: free tier up to 100 rows and 8 variables. Beyond that, $0.05 + $0.01 per 100 extra rows + $0.01 per extra variable squared, via x402 (USDC on Base) or MPP/Stripe. MPP/Stripe adds a flat $0.35 per-transaction fee (Stripe processing), so the MPP challenge amount in a `payment_required` response is $0.35 higher than the x402 amount for the same base price; x402 gets the lower rate. Omit `payment` for free-tier requests; paid requests without a valid credential receive a `payment_required` result with pricing and accepted schemes. Full pricing table as structured JSON: occam://pricing Advisory limits: jobs over 500,000 rows or 50 variables are accepted but may not converge within the time budget; the response carries a top-level `warning` the agent should surface and treat as tentative. If `feature_names` is supplied, its length must equal the number of data columns; a mismatch is rejected with a validation error. Rate limit: 10 requests/hour per IP, 200/hour global, max queue depth 20 (shared with pysr_run and pysr_uncertainty). Response (success) includes `equations[]` (each with `variable`, `equation`, `expression`, `expression_latex`, `r2`), `library_terms`, `nonzero_terms`, `elapsed_seconds`, `canonical_match` (dict with `system`, `form`, `variable_map`, `parameter_map`, `confidence` if the discovered system matches one of Lorenz / Lotka-Volterra / Van der Pol / Duffing; `null` otherwise), optional `warning`, optional `_meta` (MPP receipt on paid calls). Full response and payment-required schemas: occam://tool-schemas Example request: data=[[1.0, 0.0], [0.95,…
| Name | Type | Req | Description |
|---|---|---|---|
| data | array | yes | 2D array of time series data. Each row is a timestep, each column is a state variable. Free tier: 100 rows, 8 variables. Paid tier: up to 500,000 rows, 50 variables. |
| feature_names | – | – | Names for each variable/feature column. Defaults to x0, x1, ... |
| max_iter | integer | – | Maximum STLSQ optimizer iterations. Default 20. |
| payment | – | – | Payment credential. Accepts either a JSON object or a JSON-encoded string (FastMCP's transport pre-parses strings whose field annotation is non-bare-`str` into objects, so the object form is canonica… |
| poly_degree | integer | – | Polynomial library degree for SINDy candidate functions. Default 2. |
| t | array | yes | Timestamps corresponding to each row of data. Length must match row count. |
| threshold | number | – | STLSQ sparsity threshold. Higher values produce sparser equations. Default 0.1. |
| Name | Type | Req | Description |
|---|---|---|---|
| canonical_match | – | – | – |
| elapsed_seconds | – | – | – |
| equations | – | – | – |
| library_terms | – | – | – |
| nonzero_terms | – | – | – |
| warning | – | – | – |
No examples provided.
What is the Occam MCP server?
Occam is an MCP server listed in the public MCP registry as fit.occam/occam. Finds the simplest equation consistent with your data. SINDy and PySR symbolic regression via MCP. This page covers its hosted endpoint (https://occam.fit/mcp/).
Is the Occam MCP server safe to use?
Occam scores 87 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 Occam MCP server expose?
Occam exposes 4 tools: feature_request, sindy_run, pysr_run, pysr_uncertainty. Their descriptions and schemas cost roughly 3,343 tokens of context every time the server is loaded.
Does the Occam MCP server require authentication?
No. We connected to Occam without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Occam MCP server still maintained?
Occam is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.