# A seat is a contract > A seat is a party's role in a collaboration, and it is defined by a contract, never by a character. Page: Methodology · Start Canonical: https://banes-lab.com/disciplined-methodology#a-seat-is-a-contract This section is stop 9 of 102 in the learning route. Previous: [08 - Rules with names](https://banes-lab.com/disciplined-methodology/start/rules-with-names.md). Next: [10 - The behaviour document](https://banes-lab.com/disciplined-methodology/start/the-behaviour-document.md). It builds on [02 - Who does what](https://banes-lab.com/disciplined-methodology/start/who-does-what.md). A seat is a party's role in a collaboration, and it is defined by a contract, never by a character. A seat applies [design by contract](https://banes-lab.com/records/arch/design-by-contract.md) to a party: the contract is a role document with the same sections for every seat, as shown in [I1·a a role document](https://banes-lab.com/disciplined-methodology#a-seat-is-a-contract-panel-a). It names what the seat owns, what it refuses, how it works, the principles that decide its calls and the mistakes it tends to make. ### Contract over character A persona gives a model a voice, and a voice is not a behaviour. The persona keeps its voice through the whole session and still drifts as much as a session with no persona at all. A character is judged by how it sounds, and sounding right comes easily to a model even when the work underneath is wrong. For this reason I get [consistency](https://banes-lab.com/records/arch/consistency.md) from checks rather than from roleplay. A seat is defined by its contract rather than by its character. In practice, a role is a short document with the same sections every time, and it names the mistakes that seat is known to make beside what it owns. The seat's output is checked against the contract, never against its tone. The seat's identity stays out of the filename, so that handing a role over changes a field rather than a path. To check this, strip the voice from a session's output and check what remains against the contract. Whatever the voice was hiding becomes visible. A measured mistake is evidence and is kept in one place: it leaves a role document only by being moved to the [one home](https://banes-lab.com/disciplined-methodology/build/one-home.md) history has. A mistake that is only expected never replaces one that was measured. A uniform shape is what makes a set of seats comparable. A reader looking for what a seat refuses finds it in the same place in every document; otherwise the documents are just prose filed together. The set of sections is the contract, and the declared fields are what a tool reads: the identity, the concern the seat holds, and the one line another seat uses to route work to it. The seat's identity is allocated and recorded before its first write, for the reasons [coordination is software](https://banes-lab.com/disciplined-methodology/collaborate/coordination-is-software.md) gives. The section that matters most is the one about what the seat gets wrong. A reviewer that approves a change because it reads well, a builder that reviews the description instead of the diff, and a coordinator that routes work a single edit would have closed are all measured mistakes. A seat is given its own document before its first edit so that it can avoid repeating them. A contract without that section is a job description, and a job description does not constrain the seat at all. I1·a a role document ```markdown # Reviewer ## The seat's identity, bound in the index before its first write. ## The list of findings, and nothing else. ## A change ships only once the list is empty. ## One finding per line: file, line, expected, found. No style comments, no rewrites. ## Affirming a change that reads well. Reviewing the description instead of the diff. ## A finding without a location is an opinion. Approval is what remains when the list is empty. ``` ## Links to - [Design by Contract](https://banes-lab.com/records/arch/design-by-contract.md) - [One home](https://banes-lab.com/disciplined-methodology/build/one-home.md) - [Consistency](https://banes-lab.com/records/arch/consistency.md) - [Coordination is software](https://banes-lab.com/disciplined-methodology/collaborate/coordination-is-software.md) ## Linked from - [Orchestration invariants](https://banes-lab.com/pag/orchestration/orchestration-invariants.md) - [Agents as executed contracts](https://banes-lab.com/disciplined-methodology/collaborate/agents-as-executed-contracts.md) - [Coordination is software](https://banes-lab.com/disciplined-methodology/collaborate/coordination-is-software.md) - [Proxies give way](https://banes-lab.com/disciplined-methodology/ship/when-not.md)