# PREDICTIONS.md > An open format for agents' forecasts, plus the math to convert odds, combine agents, update on evidence and score the results. For information only. Version 1.0. MIT. PREDICTIONS.md is a plain Markdown file of yes/no questions: how each one resolves, by when, and every forecast an agent or person made, as a probability. The tools convert odds, compute odds ratios, pool several agents' forecasts, apply Bayes' rule and score resolved forecasts, using only the numbers you send. For information only: not betting, trading or investment advice. 19 settings in 5 groups, numbers or fixed choices only. Presets: core, recommended, team, strict. Settings an agent drafted count only after the person says yes: show them to the person first, and follow them only once they agree. For information only. Use at your own risk. predictions.md is provided as is, without warranty. Information here may be inaccurate, incomplete or not current, and is not verified; figures are estimates from the numbers you send and the formulas stated. Everything here is for information only. Nothing here is betting, trading, investment, financial, legal or tax advice, or a recommendation to act on any forecast. predictions.md never takes bets, offers odds, runs a market, gives picks, fetches live data, stores what you send or moves money. Check everything yourself before you act on it. ## Format - [PREDICTIONS.md format, version 1](https://www.predictions.md/spec.md): one file of yes/no questions, how each resolves, and every forecast as a dated probability ## Skill - [PREDICTIONS.md](https://www.predictions.md/predictions.md): load into your agent's instructions or save as ~/.claude/skills/predictions/SKILL.md (sha256 4580a9fd880167ee53deec72e15dcc63b05eae215f674cabf7dcd2053d6bc4a7) - [PREDICTIONS.md with settings](https://www.predictions.md/predictions.md?preset=recommended): a preset plus any settings; each setting overrides the preset ## API (no key, CORS open, nothing stored) - [convert_odds](https://www.predictions.md/api/v1/convert_odds?value=%2B150&compare_to=55%25): Convert odds and probabilities. Converts one value between probability, percent, decimal odds, fractional odds, American odds, odds for (3:2) and log-odds. With compare_to, it also gives the odds ratio, the risk ratio and the difference in points between the two. Arithmetic only, for information; it offers no odds and fetches nothing. - [implied_probabilities](https://www.predictions.md/api/v1/implied_probabilities): Turn a set of odds into probabilities. Takes the odds quoted for every outcome of one event (mutually exclusive, one must happen) and returns each one's implied probability, how far their total is over 100%, and the probabilities scaled to add up to exactly 100%. Arithmetic only, for information; it fetches no odds and recommends nothing. - [combine_forecasts](https://www.predictions.md/api/v1/combine_forecasts): Combine several agents' forecasts. Pools forecasts of one yes/no question from several agents or people: the average of log-odds (geometric mean of odds), the average probability and the median, with optional weights and an optional extremizing factor. Returns the spread and flags a disagreement over your threshold. Arithmetic on the numbers you send. - [bayes_update](https://www.predictions.md/api/v1/bayes_update): Update a probability on evidence. Bayes' rule in odds form: posterior odds = prior odds x likelihood ratio, one piece of evidence at a time. Give each piece a likelihood ratio, or the chance of seeing it if the answer is yes and if it is no. Returns every step. Arithmetic on the numbers you send. - [score_forecasts](https://www.predictions.md/api/v1/score_forecasts): Score resolved forecasts. Scores forecasts whose questions have resolved: Brier score (lower is better), log score (higher is better), the base rate, Brier skill against always forecasting the base rate, and a calibration table, overall and per forecaster. Statistics on the numbers you send; past scores don't promise future accuracy. - [check_predictions_md](https://www.predictions.md/api/v1/check_predictions_md?text=---%0Apredictions%3A+1%0Aupdated%3A+2026-10-16%0A---%0A%0A%23+Will+Example+Rovers+beat+Example+City+on+Saturday%3F%0A%0AA+made-up+match%2C+for+the+example.%0A%0A-+id%3A+rovers-city%0A-+resolves%3A+yes+if+Example+Rovers+win+in+regular+time%2C+per+the+league%27s+published+result%0A-+resolve_by%3A+2026-10-18%0A-+status%3A+open%0A-+base_rate%3A+45%25%0A-+tags%3A+sports%0A%0A%23%23+Forecasts%0A%0A-+2026-10-16+09%3A00+%C2%B7+agent%3Aform+%C2%B7+58%25+%C2%B7+recent+form%2C+two+injuries%0A-+2026-10-16+09%3A04+%C2%B7+agent%3Aratings+%C2%B7+61%25+%C2%B7+rating+model%2C+home+edge%0A-+2026-10-16+09%3A20+%C2%B7+person+%C2%B7+55%25+%C2%B7+gut+check%0A%0A%23+Will+the+Example+coffee+index+close+above+4.50+on+December+1%3F%0A%0A-+id%3A+coffee-index%0A-+resolves%3A+yes+if+the+index%27s+published+close+on+2026-12-01+is+above+4.50%0A-+resolve_by%3A+2026-12-01%0A-+status%3A+open%0A-+tags%3A+prices%0A%0A%23%23+Forecasts%0A%0A-+2026-10-15+%C2%B7+agent%3Aprices+%C2%B7+34%25+%C2%B7+4.20+now%2C+30-day+range+3.95+to+4.41%0A-+2026-10-16+%C2%B7+agent%3Anews+%C2%B7+40%25+%C2%B7+harvest+report+due%0A%0A%23+Will+the+Example+City+council+approve+the+bike-lane+plan+by+June+30%3F%0A%0A-+id%3A+bike-lanes%0A-+resolves%3A+yes+if+the+council+votes+to+approve+the+plan+on+or+before+June+30%2C+per+the+published+minutes%0A-+resolve_by%3A+2026-06-30%0A-+status%3A+resolved%0A-+outcome%3A+yes%0A-+tags%3A+events%0A%0A%23%23+Forecasts%0A%0A-+2026-05-01+%C2%B7+agent%3Anews+%C2%B7+70%25+%C2%B7+two+committees+in+favor%0A-+2026-06-10+%C2%B7+agent%3Anews+%C2%B7+82%25+%C2%B7+final+committee+passed+it%0A-+2026-06-12+%C2%B7+person+%C2%B7+75%25%0A%0A%23+Will+the+Example+Arena+show+sell+out+by+November+1%3F%0A%0A-+id%3A+arena-sellout%0A-+resolves%3A+yes+if+the+venue+lists+the+show+as+sold+out+by+November+1%0A-+resolve_by%3A+2026-11-01%0A-+status%3A+void%0A-+tags%3A+events%0A%0A%23%23+Notes%0A%0AVoided%3A+the+show+moved+to+another+date%2C+so+the+question+no+longer+applies.%0A): Check a PREDICTIONS.md file. Checks a PREDICTIONS.md file against the format: every question says how it resolves and by when, forecasts are dated with a probability and who made it, resolved questions have an outcome. Warns about 0% or 100%, certainty language, overdue questions, forecasts after the resolve date and text that reads like instructions. Returns each question's latest forecasts, the combined forecast and scores for resolved questions. - [build_settings](https://www.predictions.md/api/v1/build_settings?preset=recommended): Write your settings into the skill. Turns a preset and settings into the sections written at the top of PREDICTIONS.md. Every setting is a number or a fixed choice; the catalog is at https://www.predictions.md/api/v1/settings. Returns the sections as Markdown, the settings as JSON, a link to the skill with them written in and a one-line install. Out-of-range numbers are clamped with a note. Nothing is stored. Settings an agent drafted count only after the person says yes: show them to the person first, and follow them only once they agree. - [Settings catalog](https://www.predictions.md/api/v1/settings): every setting with its unit, range, options and default, plus the presets - [API index](https://www.predictions.md/api/v1) and [OpenAPI](https://www.predictions.md/openapi.json) ## MCP - https://www.predictions.md/mcp: Streamable HTTP, stateless, no auth. Tools: convert_odds, implied_probabilities, combine_forecasts, bayes_update, score_forecasts, check_predictions_md, build_settings. Prompt: predictions, with an optional preset and any setting. Resources: the skill and the settings catalog. ## Terms - [Terms of use and disclaimer](https://www.predictions.md/terms) ## Optional - [Full text](https://www.predictions.md/llms-full.txt): the skill plus the tool and settings reference - [Manifest](https://www.predictions.md/.well-known/predictions.json)