Reserve an operation resource budget

Core meaning

Capability purpose: Prevent concurrent or long-running work from silently exceeding the resource amount available to its approved scope.
Meaningful outcome: A reservation is active, adjusted, consumed, released, expired, denied, or failed with operation binding, unit, amount, authority basis, time bounds, and remaining allowance.
Boundaries — includes: reservation identity, operation/run binding, budget owner or scope, resource unit, amount, approval/policy reference, expiry, adjustment, consumption linkage, release, denial, and conflict handling.
Boundaries — excludes: estimating cost, granting action authority, measuring actual usage, billing/payment holds, executing the operation, and deciding domain completion.
Terms and concepts: A resource reservation is an internal operational hold. It is not a financial authorization unless a separate commercial realization explicitly defines it that way.

Actor: An authorized execution coordinator, budget service, workflow, or agent acting under an accepted request or standing policy.
Command / intent: Create, adjust, consume against, release, or expire a resource reservation for one operation.
Current state: The operation identity, eligible budget scope, requested amount/unit, existing reservations, authority basis, expiry policy, and current availability can be determined.
Policies / invariants: A reservation does not authorize an otherwise unauthorized action; operation and budget scope remain bound; the same allowance is not silently double-reserved; adjustments are attributable; expiry and release are explicit; actual usage remains separately observed and reconciled.
Transition: Validate authority and availability, create or update the bounded hold, and record its new state and remaining allowance.
Result: An active, adjusted, consumed, released, expired, denied, or failed reservation.
Events / effects: May permit execution to begin or continue, pause work at a boundary, or trigger owner attention when capacity is insufficient.
Unknowns: Universal reservation concurrency, overcommit, extension, expiry and recovery rules are not established.

Reservation is neither spend nor billing and cannot substitute for action authorization.
Reservation changes must retain operation, authority, amount, unit and time provenance.

Expire unused reservations and release their remaining allowance when the bound operation reaches a terminal state.

Distributed reservation consistency and recovery after partial failure require realization-specific profiles.

Statement	Semantic class	Evidence status	Source / note
A resource reservation is an expiring operational hold between authorization and measured use, with its own lifecycle and failure states.	rule/invariant	sourced	R01–R03 and R05–R07.