---
title: "The market as a living system: value chains, systems models, templates and the search for product-market fit"
description: "The market as a living system: value chains, systems models, templates and the search for product-market fit: the 13 calls this system serves, each a route of the API and a tool of the MCP server, at contract 0476e35e6e275db5."
section: systems
address: /systems/26-the-market-as-a-living-system-value-chains-systems-models-templates-and-the-search-for-product-market-fit
contract: 0476e35e6e275db5
---

# The market as a living system: value chains, systems models, templates and the search for product-market fit

The market as a living system: value chains, systems models, templates and the search for product-market fit: the 13 calls this system serves, each a route of the API and a tool of the MCP server, at contract 0476e35e6e275db5.

[figure: The market as a living system: value chains, systems models, templates and the search for product-market fit: 13 calls of the contract, by family.]

# The market as a living system: value chains, systems models, templates and the search for product-market fit

The 13 calls below are the whole of this system on the wire: each is one route of the API and one tool of the MCP server, with one typed input, one card as its answer and one refusal shape. Every answer carries its foot: what was read, the population and the control.

## The calls



| tool | route | takes | gives |
|---|---|---|---|
| [si.read.fit_frame](/reference/tools/si-read-fit_frame) | [POST /v1/read/fit_frame](/reference/read/fit_frame) | Reads the frame of one fit search | The answer gives the markets ranked, the offering sculpted for each buyer profile, the tactics proposed to test the fit, the verdict for each market, and the set of options that compares them |
| [si.read.fit_plays](/reference/tools/si-read-fit_plays) | [POST /v1/read/fit_plays](/reference/read/fit_plays) | Reads the tactics that fit one phase of the search, for a vertical or a kind of offering | The answer gives the tactics in the order to run them |
| [si.read.market_twin](/reference/tools/si-read-market_twin) | [POST /v1/read/market_twin](/reference/read/market_twin) | Reads one market twin, and the date to read it as of | The answer gives the twin: the model family and template it was instanced from, the participants placed on the chain, the level of every stock as of the date, the simulations run on it in order, and the strategy whose armed plays are its interventions |
| [si.read.model_families](/reference/tools/si-read-model_families) | [POST /v1/read/model_families](/reference/read/model_families) | Reads the model families that fit a vertical or a representation | Each family arrives with what it represents, the substrate it is written over, its solver and its check |
| [si.read.simulation_frame](/reference/tools/si-read-simulation_frame) | [POST /v1/read/simulation_frame](/reference/read/simulation_frame) | Reads the frame of one simulation | The answer gives the trajectory of every stock, the gain of every loop, the sensitivity to every intervention, and the set of options that compares strategies laid over the same template |
| [si.read.systems_models](/reference/tools/si-read-systems_models) | [POST /v1/read/systems_models](/reference/read/systems_models) | Reads the systems models that fit one vertical or one kind of offering | Each template arrives with its readiness and the defect it carries named |
| [si.read.value_chain](/reference/tools/si-read-value_chain) | [POST /v1/read/value_chain](/reference/read/value_chain) | Reads the value chain of one vertical, with the brand whose participants are placed on it | The answer gives the chain's stocks and handovers with their counts, the participants on each stock, and the loops the templates name over it |
| [si.act.make_market_twin](/reference/tools/si-act-make_market_twin) | [POST /v1/act/make_market_twin](/reference/act/make_market_twin) | Makes one market twin from a vertical, a segment, a brand, a template and the way of going to market it serves | The answer gives the twin, ready or not ready with the stock the record cannot read named |
| [si.act.place_participant](/reference/tools/si-act-place_participant) | [POST /v1/act/place_participant](/reference/act/place_participant) | Places one party in one role on one stock of a vertical's chain, with the evidence for it | The answer gives the participant, ready or not ready with the reason |
| [si.act.record_fit_reading](/reference/tools/si-act-record_fit_reading) | [POST /v1/act/record_fit_reading](/reference/act/record_fit_reading) | Records one result of a person's own test: the tactic, the market, the measure, its value, the sample and where it came from | The answer gives the reading as a fact the record keeps |
| [si.work.lay_strategy](/reference/tools/si-work-lay_strategy) | [POST /v1/work/lay_strategy](/reference/work/lay_strategy) | Lays one strategy on one twin, with the bounds of the run | The call returns the simulation whose interventions are the strategy's armed plays, then the frame |
| [si.work.search_fit](/reference/tools/si-work-search_fit) | [POST /v1/work/search_fit](/reference/work/search_fit) | Searches for product-market fit from one end: an offering looking for its markets, or a concept looking for a market | The call returns the search as work, then the frame that holds what it settled |
| [si.work.simulate_market](/reference/tools/si-work-simulate_market) | [POST /v1/work/simulate_market](/reference/work/simulate_market) | Runs one systems model template over a market, with the interventions to try and the bounds of the run | The call returns the simulation as work, then the frame that holds what it reached |



## The bars this system enforces

Every bar is a row of the parameter register: an administrator changes it, and the platform reads it by name at the place of enforcement the row records.

| parameter | family | dimension | enforced at |
|---|---|---|---|
| the longest horizon of a market simulation, by template | machinery | a time | the readiness gate of the simulation's input |
| the finest step of a market simulation | machinery | a time | the readiness gate of the simulation's input |
| the sample count and the time budget of a market simulation | machinery | a count, and a time | the simulation, which stops with the trajectories it reached |
| the level of every interval a frame of a simulation reports | intend | a share | the stepping, on every trajectory |
| the bar a candidate market's score must clear to be proposed | intend | a share | the search's step of the candidate markets |
| the count of rivals running a play above which it reads table stakes | intend | a count | the tactic *alpha against table stakes*, and the class reading on the beat (stipulated at three until a market's reading sets the row) |
| the share very disappointed that reads fit | intend | a share | the tactic *the very-disappointed survey* |
| the window a fit reading stays good for, by tactic | intend | a time | the search's testing step, which marks a stale reading |
| the most tactics a search proposes per phase | intend | a count | the search's step of the plays to test |
| the retention class of a fit reading a stranger submits | receive | a retention class row | the write of a fit reading from a form |
| the fewest participants for which the stocks-and-flows run stands in for the agents' run | machinery | a count | the readiness gate of the twin's family (MODELS/the-market-as-a-formal-model.md section 4) |
| the fewest units a stock holds before its flows step deterministically | machinery | a count | the stepping, per stock and step |
| the stages of a delay | machinery | a count | the stepping of a delayed flow |
| the fewest sequences a learned latent model needs, and the shortest length of a sequence | machinery | a count, and a count | the readiness gate of the sixth model family |
| the off-path error a learned latent model may not exceed, as a multiple of its on-path error | intend | a number | the readiness gate of the sixth model family, on held-out counterfactual play sequences |
| the strength of pooling toward a parent segment | intend | a count | the estimator of a hazard |
| the tolerance of interval coverage | intend | a share | the coverage check on the beat |
| the draws of a simulation-based calibration | machinery | a count | the check on an estimator before any real count reaches it |
| the fewest ready families an ensemble needs, and the step of the coverage adjustment | intend | a count, and a share | the frame's composition when a family reads not ready for coverage, and the interval's adjustment under drift |
| the exploitability tolerance of a solved game, and the most rounds of its solver | machinery | a share of the payoff's scale, and a count | the solver of the game of roles and of the mean-field game |
| the propensity floor of a randomised play | intend | a share | the planner of the learned latent model |
| the ratio of variance to mean above which an inflow draws as a negative binomial | machinery | a number | the stepping of an absolute inflow |