Constant NODE_COUNT_LIMIT 

pub const NODE_COUNT_LIMIT: u64 = github_graphql_node_count::NODE_LIMIT; // 500_000u64

The most nodes any one document this source sends may be asked to return.

GitHub’s own published per-query ceiling, taken from github_graphql_node_count::NODE_LIMIT rather than written out again here, so this workspace cannot hold a stale copy of somebody else’s number. A query above it is refused before it is executed, whoever is asking and whatever board they are asking about — so this is a bound on the documents rather than a budget that runs out.

This is nodeCount, the maximum number of nodes one query may return. It is not cost, the rate-limit points a call spends against an hourly allowance shared by everything the credential does — two numbers against two limits, and this constant bounds only the first. The second is computed offline too, per document: worst_case_point_cost, pinned for every document in graphql::DOCUMENTS by tests/point_cost.rs, and reconciled against GitHub’s own cost by the credentialed lane. There is no constant like this one to hold a price under, because points are an hourly allowance rather than a per-call bound.

Neither is a session’s price. What session-cost.md records of a whole session is its requests and its worst-case nodes; what a whole session spends in points is reported only by a credentialed run’s own x-ratelimit-* headers, through accounting. The module section on the three ways this source reaches an item says how the count is arrived at, and which of the page sizes below decide it.