[tylercschneider]

One Sentence Summary

A developer writing a host app's hubs can now declare the JSON Schema of each exposed method's answer, and of the answer it gave at each older major version, so a client in another repo can test against it.

ACs Covered

• A hub can expose a method with the shape of its answer, written as a JSON Schema.
• A hub can give each earlier answer the shape of the answer at that major, written the same way.
• An interface gem reading an exposed method gets its answer shape and each earlier answer's shape.
• A method or earlier answer declared with no shape reads as having none.
• The hub_kernel-mcp tool list and tool calls stay unchanged, which still needs a check in hub_kernel-mcp.

Decision Log

How does a hub declare the JSON Schema shape of an exposed method's answer?

It passes the schema as an optional answer shape keyword beside takes and writes on the exposes line, over a separate declaration method.

How does a hub give an earlier answer, the translation of a method's answer for an older major version, the shape of the answer at that major?

Each earlier answer may be given as a translation together with an answer shape, while a translation given alone still declares an earlier answer with no shape, over a second keyword listing shapes by major number.

Code Example

exposes(name, takes:, writes:, earlier_answers: {}, answer_shape: nil)

Out of Scope

• Showing shapes to callers belongs to hub_kernel-api.

Ticket Billed Against

Not specified.

Tokens Used

• Input: 74
• Output: 15,069
• Cache read: 3,329,026
• Cache write: 41,494
• Total: 3,385,663

Effort

• Sessions: 0
• Prompts: 0
• Words typed: 0
• Pasted blocks: 0
• Words pasted: 0
• Questions answered: 0
• Interruptions: 0
• Rejected tool calls: 0
• Claude working time: 0m
• Your active time: 0m

Time Spent

• Total: 1m
• Waiting on the owner: 0m
• Model time: 0m
• Worktree setup: 0m
• Reading: 0m
• Test-first cycles: 0m
• Commits: 0m
• Ticking criteria and recording decisions: 0m
• Full-suite checks: 0m
• Other tool calls: 1m
• pr-scribe: 0m

Closes #26

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Generation Metadata

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