About Canli Validation
Canli Validation is an MCP server for coding agents and other clients to check backtests with statistical validators and local analysis tools. Results include stated limits and, for API validations, signed receipts; a local mode computes without sending data to the API.
Key features
- 01Deflated Sharpe and overfitting checks
- 02Data-snooping tests across variants
- 03Track-record and backtest-length checks
- 04Combined backtest audit
- 05Local return-series analysis tools
- 06Signed receipt verification
Use cases
- 01Assess a Sharpe ratio after accounting for tried variants
- 02Test many strategies for data snooping
- 03Audit a backtest using several validators
- 04Verify a validation receipt offline
MCP support
Exposes validation, audit, receipt, status, financial-history, and local lab tools to MCP clients. It can use the hosted API, run locally without API submission, or connect through the hosted MCP endpoint.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://canlicapital.com/mcpclaude mcp add --transport http arhancanli-canli-validation https://canlicapital.com/mcp{"mcpServers":{"arhancanli-canli-validation":{"type":"http","url":"https://canlicapital.com/mcp"}}}Open in Cursor{"servers":{"arhancanli-canli-validation":{"type":"http","url":"https://canlicapital.com/mcp"}}}Open in VS Code{"mcpServers":{"arhancanli-canli-validation":{"type":"http","url":"https://canlicapital.com/mcp"}}}{"mcpServers":{"arhancanli-canli-validation":{"serverUrl":"https://canlicapital.com/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
https://canlicapital.com/mcpAuth requiredTools
18| Parameter | Type | Required | Description |
|---|---|---|---|
| skew | number | No | Skewness of returns; 0 if Normal. |
| returns | array | No | Periodic returns as fractions (0.01 = 1%), oldest first; replaces the Sharpe, observations, skew and kurtosis. |
| observations | integer | No | Number of return observations. |
| periods_per_year | number | No | Periods per year: 252 daily, 365 crypto, 52 weekly, 12 monthly. |
| non_excess_kurtosis | number | No | Kurtosis, not excess kurtosis; 3 if Normal. |
| observed_sharpe_annualized | number | No | Annualized Sharpe as observed. |
| effective_independent_trials | integer | No | Independent variants tried before choosing this one. |
| cross_trial_sharpe_sd_annualized | number | No | Standard deviation of annualized Sharpe across those trials. |
Details
From the project READMEcanli-validation-mcp
Is your best backtest real, or just the luckiest of the variants you tried? This MCP server lets Claude, Cursor or any MCP client answer that with the standard corrections: the deflated Sharpe ratio, the CSCV probability of backtest overfitting, data-snooping tests on every variant tried (Hansen's SPA, White's Reality Check, Romano-Wolf StepM), the minimum track record length, the haircut Sharpe ratio, and luck-equivalent trials. Free and MIT-licensed.
Quick start
# Claude Code, computed on your machine: no key, nothing sent anywhere
claude mcp add canli-local --env CANLI_LOCAL=1 -- npx -y canli-validation-mcp
# the same tools with signed, stored receipts from the free API (a free key is issued on first use)
claude mcp add canli -- npx -y canli-validation-mcp
# nothing to install: the hosted endpoint
claude mcp add --transport http canli https://canlicapital.com/mcp
Then ask, for example: "I tried 229 variants and kept the best: an annualised Sharpe of
1.5 over 730 daily returns (365 a year), skew -0.5, kurtosis 5, and the variants'
Sharpe ratios spread by 0.57. Is it real?" The assistant calls validate_deflated_sharpe: the
best of 229 skill-less variants would reach 1.60 by luck alone, so the probability that the
Sharpe is above zero falls from 98.1% to 44.4% once the search is counted. Claude Desktop and any
other stdio client (Cursor, VS Code) run the same npx command; see "Claude Desktop" and
"Generic stdio client" below.
What it does
An MCP (Model Context Protocol) server over canlicapital.com's free, keyed validation API, with a lab that computes on your machine. It gives a coding agent twenty tools: issue a free key, run the nine validators (deflated Sharpe, CSCV overfitting, data-snooping tests (Hansen's SPA, White's Reality Check and Romano-Wolf StepM), paper-evidence conformance, breadth ceiling, minimum track record length, minimum backtest length, haircut Sharpe ratio, luck-equivalent trials), audit one backtest with several of them in a single call, verify a receipt's signature offline, read service status, read a company's reported financial history from SEC filings, and six lab tools: backtest a rule over a parameter grid, summarize a long series, stress-test a strategy's returns, check a plan against a broker's limits, check a signal for lookahead, and test a whole research pipeline on placebo data. Every validation result carries, beside the number, the sentences that say what it does not establish and the receipt that records it, success or error, so the agent cannot see a number without its limits.
This package is published to npm as canli-validation-mcp.
Also listed on the official MCP Registry (io.github.arhancanli/canli-validation-mcp) and
cursor.directory. Run it with npx, no install step, as shown below. A local checkout is only needed to develop or
test this package itself; see "Local checkout" near the bottom.
This README describes the version in package.json. Unversioned npx runs npm's latest
release; npx -y canli-validation-mcp@<version> pins one.
How well agents use it
A fixed benchmark gives models these tools and scores whether they pick the right one and return
the right answer, against ground truth computed from the same checked code. Results for three
models, with every run recorded, are in
bench/agent/README.md.
What the API is (and is not)
The engine is the product. The service runs your submitted numbers through the same honesty
arithmetic canlicapital.com's own paper record runs on itself and hands back a verdict anyone can
recompute from the receipt. It signs every receipt, does not accept market data, does not
grade a strategy, and never saw your data source, its costs, or any lookahead in how a series was
built. See docs/superpowers/specs/2026-09-05-developer-key-validation-api-design.md in the main
repository for the full design.
Tools
Unreleased source adds local journal binding to validate_paper_evidence: run
CANLI_LOCAL=1 node mcp/src/server.mjs from the repository, and send exactly one of record
or record_file, plus journal_file to check source hashes, signatures and recomputed claims.
record_file accepts a standard record, a {record,signature} envelope, or the full execution
export bundle; companion metrics/observations are checked for full bundles. Signed records
need the detached signature. bindings.all_match must be true for source validation to pass.
Without a journal, the result explicitly reports structure-only conformance. Files and
signatures are refused in hosted/remote mode and never uploaded. Local results have no Canli
receipt. The current npm/hosted release retains the existing record-only API.
| Tool | Calls | Key required |
|---|---|---|
get_key | POST /api/v1/keys (listed only when no key is configured) | no |
validate_deflated_sharpe | POST /api/v1/validate/deflated-sharpe | yes |
validate_overfitting | POST /api/v1/validate/overfitting | yes |
validate_paper_evidence | POST /api/v1/validate/paper-evidence | yes |
validate_breadth | POST /api/v1/validate/breadth | yes |
validate_track_record | POST /api/v1/validate/track-record | yes |
validate_backtest_length | POST /api/v1/validate/backtest-length | yes |
validate_haircut_sharpe | POST /api/v1/validate/haircut-sharpe | yes |
validate_luck_trials | POST /api/v1/validate/luck-trials | yes |
validate_reality_check | POST /api/v1/validate/reality-check (a matrix_file is read on your machine and sent as numbers) | yes |
audit_backtest | the deflated Sharpe and track record routes, then the headline: with variants, the overfitting and data-snooping routes; without, luck trials. One validation each | yes |
verify_receipt | GET /api/v1/receipts/{id} when given an id (include_receipt returns the stored receipt); the checks run locally | no |
service_status | GET /api/v1/validate/status | no |
company_financial_history | GET /company-data/{cik}.json (a ticker resolves through GET /api/v1/company-tickers.json) | no |
validate_deflated_sharpe accepts exactly one of two input shapes, never a mix of both:
- the seven contract fields:
observed_sharpe_annualized,observations,periods_per_year,skew,non_excess_kurtosis,effective_independent_trials,cross_trial_sharpe_sd_annualized; - or a return series plus the trials behind it:
returns,periods_per_year,effective_independent_trials,cross_trial_sharpe_sd_annualized.
Sending fields from both shapes, or from neither, is rejected before any request leaves the
process; see src/schemas.mjs.
validate_reality_check takes the returns of every variant the search tried, one row per period
and one column per variant, as matrix or as matrix_file (a CSV or JSON on your machine), and an
optional benchmark series; with none, variants are tested against zero. It runs three tests on one
seeded stationary bootstrap:
- Hansen's SPA: the chance that the best variant's studentized excess return is this good if no
variant has an edge, with lower and upper bounds (
spa.p_value, the consistent p-value, is the headline, andmonte_carlo_seits sampling error); - White's Reality Check: the same question without studentizing, so one volatile variant can dominate it;
- Romano and Wolf's StepM: which variants beat the benchmark, with the familywise error held at
alpha.
A result reproduces exactly from its seed. On three fixed-seed cases the p-values agree with
Python's arch 8.0 and with a numpy transcription of Hansen's formulas within Monte Carlo error, and
the StepM sets match arch's (js/snooping-core.test.js). Only the variants sent are counted: a
search that tried more than it sends makes luck look smaller than it was.
company_financial_history is different from the other tools: it reads the public company
reference at canlicapital.com, not the validation API. Give it a CIK (1 to 10 digits) to list a
company's available financial histories, or a CIK and a us-gaap concept such as Revenues to
get the observations, newest first (limit defaults to 40, maximum 200). Every observation
keeps its filing accession, form, filed date and unit, and the result carries the SHA-256 of the
original SEC response and the record's own boundary sentence: these are accounting values as
reported to the SEC, not market prices, returns or a recommendation. Companies and concepts
outside the current release return an error with the available concepts listed.
The lab: backtest, summarize, stress, feasibility, lookahead, placebos
Six tools compute in the server process itself, on your machine or on the hosted endpoint, with nothing sent to the API and no receipt stored. Each result names the SHA-256 of exactly the numbers it was computed from, and states what it does not establish.
backtest_strategyruns a rule over every parameter set in a grid, on your prices:sma_cross(fast, slow),momentum(lookback, skip),mean_reversion(window, entry_z),breakout(lookback) orbuy_and_hold, long-only or withallow_short, after a cost per unit of turnover. The position held over each period is decided from closes up to the one before it, so no rule can see the future (a test changes later prices and checks that no earlier position moves). It then validates the best variant with the number of variants this call ran, not a number someone declared: the deflated Sharpe ratio across the grid's measured Sharpe dispersion, the CSCV probability of backtest overfitting on every variant's returns, the probabilistic Sharpe and the minimum track record, next to buy and hold over the same window. At most 200 variants and 20,000 prices per call. No code is ever run: a strategy is a family plus numbers.summarize_seriesreads a long price or return series and states it in about a hundred words, plus a field for every figure: growth, volatility, Sharpe and drift t-statistic, the worst drawdown with its dates and recovery, trend, the volatility regime (terciles of its own 21-period volatility), tails, jumps (beyond six robust standard deviations), autocorrelation, stale data and, with a benchmark, correlation and beta. A five-year daily series is about 1,260 numbers; the summary is a paragraph.stress_testresamples a strategy's returns with a stationary block bootstrap (seeded, so a run reproduces exactly) and reports how often the drawdown limit breaks and the Sharpe turns negative, then applies four named scenarios with their rules stated: a crash at the equity high (default the larger of 20% and three times the worst period), volatility multiplied, the worst stretch lived twice, and positions stuck for several periods after the worst one. The fragility share is the part of resampled histories that break the drawdown limit or lose money on a risk-adjusted basis. Generative models are not used: trained on one series they memorize it or invent dynamics nobody can check.check_feasibilitychecks a plan against a real broker before it trades: the broker's published order-rate limit against the rebalance's burst of orders (Alpaca 200 a minute, Interactive Brokers about 50 a second), the minimum order (Alpaca 1 USD notional), US day-trading rules as they stand in 2026 (FINRA retired the pattern day trader rule and its 25,000 USD minimum on 4 June 2026; firms may phase in its replacement until 20 October 2027), T+1 settlement in cash accounts, each order's share of daily volume, square-root market impact (coefficient Y, default 1) with every copy of the same strategy counted, and the capital at which costs and impact eat the expected gross return. Every broker fact carries the date it was checked and its source.check_leakagefinds lookahead in a signal without seeing its code. A causal signal computed on the first n rows gives exactly the values the full run gives for those rows.planpicks the cuts (seeded, between 40% and 95% of the series); you rerun your own code on the rows before each cut, andcomparechecks every column: a value that changed when the later rows were removed used them. On your machine,columns_filetakes the path of a JSON file{cuts, columns}your script wrote (Python'sNaNreads as missing) instead of thousands of pasted numbers. The result names the pattern: future rows with their horizon (ashift(-5)reads as five rows), the full sample (a normalization, rank, scaling or fit over the whole series), or scattered rows (filling gaps backwards). On a fixed zoo of 22 pandas and statsmodels signals (config/research/leakage-zoo.json, fromscripts/research/leakage/), all 11 leaks are found with the right pattern and none of the 11 honest indicators is flagged. A pass covers only the cuts tested: survivorship, vendor revisions or a leak confined to the first rows leave no trace.placebo_testtests a whole research pipeline at once.planwrites your panel (real.csv) and 19 placebos to a new folder in the system's temporary directory: the same returns with the periods in a random order, the same order for every asset, so each asset keeps its returns and each day its cross-section, but nothing can be predicted. Run the pipeline unchanged on each, every search, filter and parameter choice included, andcompareranks its real result among the placebo results. Every choice the pipeline makes is counted, because it makes them again on every placebo. A pre-registered study chose the reordering (scripts/research/placebo/v1/,config/research/placebo-v1-evaluation.json): in all 30 combinations of simulated market and pipeline where nothing can be predicted (10,000 tests each; five return shapes, flat, drifting and with assets that differ only in their constant means; SMA, time-series and cross-sectional momentum grids), its false-positive rate at a nominal 5% was 4.6% to 5.5%. On the same markets a t-test on the best rule found an edge 10.9% to 78.9% of the time, and Bonferroni's correction 8.0% to 10.3% wherever the market drifted and 58.5% to 59.7% where assets only differed in their means. With 19 placebos the smallest p is 0.05; 99 give a finer one.
On your own machine, prices_file, series_file and returns_file take a CSV or JSON path instead
of the numbers. Only numbers are read, plus an ISO date column when the file has one, so results can
name the day a drawdown began.
The trial ledger: count every variant an agent tries
An agent can try thousands of strategy variants in an hour, and the best of them looks skilled by luck alone. How much luck depends on how many were tried and how spread out their results were, so the honest verdict on a reported winner needs the whole search. The ledger keeps it.
Turn it on with CANLI_TOOLSETS=validate,lab,ledger (or all), then:
ledger_record_trialfor every variant, as it is tried: its returns (or a returns file), or its annualized Sharpe and sample size, plus a label and its parameters. The first call creates a ledger and returns its name; reuse it. Each reply already counts the whole search so far.ledger_summaryfor the verdict: the best trial, the Sharpe that the best of that many skill-less trials reaches by luck, the best trial's deflated Sharpe ratio after counting every trial, and the probability of backtest overfitting (CSCV) when every trial has aligned returns.ledger_exportto hand the search to someone else. Each trial is chained to the previous one with SHA-256, so a removed, reordered or edited trial shows.
Ledgers are JSON-lines files under CANLI_LEDGER_DIR (default ~/.canli/ledgers); nothing leaves
your machine. Twenty variants of pure noise, recorded this way, give a best annualized Sharpe of
about 1.5, a luck-alone expectation of about 1.7 and a deflated Sharpe near 0.4: the ledger calls
that winner what it is. The statistics are the same checked code as validate_deflated_sharpe and
validate_overfitting; test/ledger.test.mjs checks both directions (noise is flagged, a real edge
among noise keeps a deflated Sharpe above 0.95).
Auditing a backtest in one call
audit_backtest takes one strategy's return series and, ideally, every variant's returns
(variants or variants_file, the dropped ones too); without them, the number of variants tried
and their Sharpe spread. The result opens with:
headline: one test chosen because its false-positive rate was measured before anyone looked at your numbers. Null Zoo v1 (scripts/research/null-zoo/v1/in the repository) drew hundreds of thousands of simulated searches from nine return shapes with known ground truth; the bar and the rule that picks the test were committed before the run. With variants the headline comes from the data-snooping tests (validate_reality_check, with its receipt); without, from luck trials with Lo's autocorrelation correction. Its sentence quotes the measured false-positive rate for returns shaped like yours, and the worst across the nine shapes.fix_next: at most five next steps, each{id, why, next}with a stable id.computed: Lo's adjusted Sharpe, a stationary-bootstrap 95% interval for the Sharpe, the haircut Sharpe, the minimum backtest length and, with variants, how many independent trials they count as (Li and Ji) and the selected variant's out-of-sample decay.
Then the checks: validate_deflated_sharpe on the series (an estimate), validate_track_record
on the Sharpe, skew and kurtosis that check derived and, with variants, validate_overfitting.
Each is exactly what its own tool returns, with its own receipt; the deflated Sharpe runs with the
larger of the declared and counted trials and Sharpe spread, so a search cannot be made to look
smaller than it was. A check that refuses or cannot be reached is reported as that check's error.
The audit adds no grade of its own. Through the API it uses one validation per check.
When the server runs on your machine, returns_file and variants_file take the path of the
backtest's output instead of the numbers: a CSV (comma, semicolon or tab separated, with or without
a header; date and label columns are ignored, an unnamed or counting index column is skipped and
reported) or a JSON array. returns_column picks the column when there are several. Only the
numbers are read; the hosted endpoint refuses file paths. An agent copying a long series into a
call can drop values, and the copy costs tokens; in our agent benchmark, reading the file instead
took three audit questions from 4 of 9 to 8 of 9 answered correctly on gpt-5.4-mini.
Prompts, resources and structured results
Clients that show MCP prompts offer eight guided workflows: validate_backtest (deflated Sharpe, then
overfitting, then the track record needed, reported with what each number does not establish),
track_record_needed, backtest_and_validate, stress_my_strategy, production_check,
summarize_market_series, check_signal_for_lookahead and test_pipeline_on_placebos. Resources: canli://limits, the boundary sentences every result carries;
canli://sources, the papers behind each validator and how each is checked against them;
canli://strategy-spec, the JSON Schema of every strategy family and its parameters; and
canli://openapi, the API's OpenAPI 3.1 document. Two resource templates are for writing code
against the tools: canli://schemas/{tool} returns a tool's exact input and output JSON Schema, and
canli://examples/{language}/{tool} a working call in python, javascript or curl (both
variables complete). A test compiles every generated Python and JavaScript example and checks that
every example's arguments are valid input. Every tool result carries its envelope both as text and
as structuredContent.
Compact context (0.3.0)
An agent pays for every token a tool returns, including whitespace it never reads. Since 0.3.0
every result is minified JSON, and a company history returns its observations as one columns
header and one row per observation, with a unit shared by every row stated once. No field is
dropped: every boundary sentence, accession number, form, filed date and source hash is still in
the result, and columns + rows rebuild each observation exactly.
Measured with bench/token_cost.py on live records (tokenizer: tiktoken o200k_base; other
tokenizers give different absolute counts), 20 observations each:
| Record | 0.2.0 (indented) | minified | 0.3.0 (minified, columnar) |
|---|---|---|---|
| Apple, StockholdersEquity | 2,214 | 1,560 (−29.5%) | 1,060 (−52.1%) |
| Microsoft, CashAndCashEquivalentsAtCarryingValue | 2,231 | 1,574 (−29.4%) | 1,065 (−52.3%) |
The validation tools gain the minification only: the live service_status envelope measured 593
tokens indented and 475 minified (−19.9%); their boundary sentences are kept word for word. These
are measurements of these results, not a claim about any other server.
Breaking change from 0.2.0: history.observations is now {unit?, columns, rows} instead of
an array of objects.
Configuration
| Variable | Default | Meaning |
|---|---|---|
CANLI_API_BASE | https://canlicapital.com | Where the API lives. Point it at a preview deployment for testing. |
CANLI_KEY | unset | A key already issued from POST /api/v1/keys. When set, get_key sends no request and reports the key is already configured; every other tool sends it as Authorization: Bearer <key>. |
CANLI_FULL_ENVELOPE | unset | 1 or true returns each validation's full API envelope instead of the compact result (below). |
CANLI_TOOLSETS | all | Which tools to list: a comma-separated choice of validate, receipts, company, status and lab, or all. An unknown name is refused at startup. See "Toolsets" below. |
CANLI_LOCAL | unset | 1 or true runs the eight validators on this machine (private local mode, below): no key, no network, no receipt. |
If CANLI_KEY is not set and local mode is off, call get_key once per session before the validators. The key it
returns lives only in this process's memory for the life of the session; it is not written to
disk.
HTTP failures and API error envelopes are marked as MCP tool errors while preserving the complete JSON envelope. A successful validation with a negative verdict remains a normal result. Requests have a 30-second deadline covering headers and body, reject redirects, and are never retried automatically. A timeout may occur after the service has processed a request; check service status before deciding to submit again. Non-JSON response bodies and raw network errors are omitted from tool errors.
Install
No install step. npx fetches the published package on first run, so every client config below
just spawns npx -y canli-validation-mcp. See "Local checkout" near the bottom to develop or test
this package itself instead of running the published one.
Hosted endpoint (no install)
The same tools are served at https://canlicapital.com/mcp over MCP Streamable HTTP, for clients
that connect to a URL instead of spawning a process (Claude.ai connectors, ChatGPT, Cursor's remote
servers). Nothing to install, and no Node.js on your machine.
claude mcp add --transport http canli https://canlicapital.com/mcp
Without a key, requests run under a shared anonymous key, so the daily validation quota is shared by every hosted caller. When that shared quota is used up for the day, validations are still answered, computed by the same code on the hosted endpoint, but without a stored receipt; the result says so. For your own quota, issue a free key (see /developers) and send it as a header:
claude mcp add --transport http canli https://canlicapital.com/mcp --header "Authorization: Bearer $CANLI_KEY"
Add ?toolsets= to the URL to list only some tools (see "Toolsets" below), for example
https://canlicapital.com/mcp?toolsets=company.
The endpoint is stateless. On it, get_key issues nothing and says which key is in use, because a
key issued there would not reach the next request. A malformed Authorization header is refused
rather than replaced with the shared key.
Claude Desktop
Add to claude_desktop_config.json (Settings, Developer, Edit Config):
{
"mcpServers": {
"canli": {
"command": "npx",
"args": ["-y", "canli-validation-mcp"]
}
}
}
Restart Claude Desktop afterward. Add an "env" object with CANLI_API_BASE to point this at a
preview deployment instead of the default.
Claude Code
claude mcp add canli -- npx -y canli-validation-mcp
Run claude mcp list to confirm it is registered, and claude mcp remove canli to remove it.
Private local mode
Set CANLI_LOCAL=1 and the eight validators run on your machine: nothing about the series you
submit is sent to canlicapital.com, no key is needed, and no receipt is stored. The computation is
the API's own, shipped byte for byte in src/local (a test fails if it drifts), so a local result
equals the hosted one; it names no receipt id because none was made.
claude mcp add canli-local --env CANLI_LOCAL=1 -- npx -y canli-validation-mcp
verify_receipt by id, service_status and company_financial_history still read from canlicapital.com;
they send no series. In the Claude Desktop extension this is the "Private local mode" setting.
Generic stdio client
Any MCP client that can spawn a process and speak stdio will work. Using the official SDK directly, from Node:
import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
const transport = new StdioClientTransport({
command: "npx",
args: ["-y", "canli-validation-mcp"],
env: { ...process.env, CANLI_API_BASE: "https://canlicapital.com" },
});
const client = new Client({ name: "my-agent", version: "0.1.0" });
await client.connect(transport);
const { tools } = await client.listTools();
console.log(tools.map((t) => t.name));
const keyResult = await client.callTool({ name: "get_key", arguments: { label: "my-agent" } });
if (keyResult.isError) throw new Error("Key setup failed; inspect the error privately.");
// The session retains the issued key. Avoid printing its envelope into logs.
const result = await client.callTool({
name: "validate_deflated_sharpe",
arguments: {
returns: [0.004, -0.002, 0.007, 0.001, -0.003, 0.005, 0.002, -0.001],
periods_per_year: 252,
effective_independent_trials: 30,
cross_trial_sharpe_sd_annualized: 0.5,
},
});
console.log(result.content[0].text); // the answer, its limits and its receipt
await client.close();
What a result does not establish (boundary language)
Every envelope this server returns carries these sentences, verbatim, from the API itself
(api/_lib/limits.js):
- This verdict is about the series exactly as submitted. The service never saw the data source, its costs, survivorship, or any lookahead in how the series was built.
- A deflated Sharpe or overfitting probability above or below any threshold is not admission to anything and is not a forecast.
- The receipt is content-hashed, reproducible from the open-source core it names, and signed with Ed25519 by a key published at https://canlicapital.com/.well-known/canli-receipt-keys.json.
- Quotas: 1000 validations per key per UTC day, 5 keys per client per UTC day, 1048576 bytes per validation request, 1024 bytes per key revocation request, 20000 observations per series, 200 variants per matrix.
Each tool's description also states one of these sentences, so an agent sees the boundary before it calls the tool, not only after.
Compact results (tokens)
A validation result is the answer (data), the sentences above except the quota line, and the
receipt's id and URL; an error keeps its error. The rest of the API envelope (schema, endpoint,
timestamps, claim and capital class, the human page, the source-file hashes and the quota line)
describes the service rather than the answer, and an agent pays for every token of it on every
call. It stays in the stored receipt, which verify_receipt returns in full with include_receipt, and in service_status.
On a breadth result this is about half the text. Set CANLI_FULL_ENVELOPE=1 to receive every field.
Toolsets (tokens)
A client sends the model the whole tool list on every turn, and it is most of each turn's prompt:
a validation result is a few hundred tokens, the list of every tool several thousand. A client
that needs one kind of tool can list only that kind, with CANLI_TOOLSETS (stdio) or
?toolsets= (hosted endpoint). The default is every toolset except company, whose one tool
canli-fundamentals-mcp does better and point in time, and ledger, which keeps files on your machine
and is local only; all adds both. get_key is listed only when
no key is configured.
| toolset | tools |
|---|---|
validate | get_key, the nine validators, audit_backtest |
receipts | verify_receipt |
company | company_financial_history |
status | service_status |
lab | backtest_strategy, summarize_series, stress_test, check_feasibility, check_leakage, placebo_test |
ledger | ledger_record_trial, ledger_summary, ledger_export (stdio only) |
Measured with bench/tool_list_tokens.py (tokenizer: tiktoken o200k_base; other models'
tokenizers give different absolute counts), in the shape an OpenAI-style client sends the list:
| CANLI_TOOLSETS | tools | tokens per turn | of all |
|---|---|---|---|
| (default) | 19 | 5,978 | 85% |
| (default, with CANLI_KEY) | 18 | 5,842 | 83% |
all | 23 | 7,019 | 100% |
validate | 11 | 3,658 | 52% |
receipts | 1 | 182 | 3% |
company | 1 | 273 | 4% |
status | 1 | 89 | 1% |
lab | 6 | 2,055 | 29% |
ledger | 3 | 772 | 11% |
Providers cache a tool list that is identical from turn to turn and bill the cached part at a
fraction of the price (test/tool-list-stable.test.mjs keeps each list byte-stable); a smaller list
costs less either way.
Local checkout
Only needed to develop or test this package itself, not to run the published one.
cd mcp
npm ci
node src/server.mjs
Point a client at the checkout instead of npm by spawning node /absolute/path/to/meridian/mcp/src/server.mjs
in place of npx -y canli-validation-mcp in any config above.
Testing
npm test
npm run test:package
Runs node --test over test/*.test.mjs: schema round-trips against the API's own OpenAPI and
manifest examples, one success, error-envelope and quota-429 case per keyed tool (a fake fetch
stands in for the network), a check that every tool description carries a limits sentence, a
check that those sentences have not drifted from api/_lib/limits.js, a check that no shipped
file contains an em dash, and one test that spawns the actual server binary and performs a real
MCP tools/list and callTool handshake over stdio against a local HTTP stub, so the wiring is
proven rather than assumed.
test:package creates the actual npm tarball, checks its exact file list and license,
installs it in a temporary consumer directory, and runs the stdio test against that
installed entry. Dependency installation contacts npm; tool calls use only the local
HTTP stub. It neither publishes a package nor issues a production API key.
Dependencies
Only @modelcontextprotocol/server (pinned exact; the MCP SDK's server package, which itself
depends only on @modelcontextprotocol/core and zod) and zod (pinned exact): four packages in
the installed tree, where 0.7 and earlier pulled in about 95 through @modelcontextprotocol/sdk.
No other runtime dependency is added, and nothing in this package touches the site's root package.json,
.vercelignore, api/, scripts/, js/, or public/.
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.