## Seed Desk\: welcome and inventory Mara’s first goal is modest\: stop repeating the fictional seed desk’s opening hours\. Her obstacle is that a friendly human command alone would leave the agent without a supported way to retrieve the same information\. She chooses two entrances to one small domain\: a human command and a read\-only tool\. ### Milestone\: a welcoming desk for both readers **Starting state\:** no reservation state\, no inventory mutation and no external service\. Files\: - [Stage 1 entry]() - [Tool description]() - [Seed Desk instructions]() **Terminal shell—launch stage 1\:** ~~~sh omp --no-extensions --no-skills -e "$EXAMPLES/seed-desk/01-welcome/index.ts" ~~~ **Human OMP slash commands—enter in the composer\:** ~~~text /seeds welcome /seeds hours ~~~ The hours response is\: **Expected local output\:** ~~~text Our fictional desk opens Saturday, 10:00-12:00. No booking has been made. ~~~ The machine interface is `seed_welcome`\. **Model tool arguments—call `seed_welcome`\:** ~~~json {"op":"discover"} ~~~ **Model tool arguments—call `seed_welcome`\:** ~~~json {"op":"inspect","topic":"hours"} ~~~ The first operation advertises `discover` and `inspect`\, the topics\, scope and quiet flag in structured `details`\. The second returns the same hours text used by the slash command\. Important distinction\: `details` is useful to SDK callers\, hosts and renderers\. It is not automatically model\-visible\. This stage’s ordinary text content tells the model which topics it can inspect\; the quiet flag is in `details`\, not duplicated into that text\. #### What the code changes The async factory reads its description from a real adjacent file\. It registers\: - `seed_welcome`\, with `approval: "read"` and `loadMode: "essential"`\; - the boolean flag `seed-quiet`\; - a `session_start` notification\; - `/seeds`\, including argument completion\. It does **not** register a reservation operation\. **Exact excerpt—completion behavior in [stage 1’s entry]()\; not a standalone replacement file\:** ~~~ts getArgumentCompletions(prefix) { const matches = choices.filter(value => value.startsWith(prefix.trimStart())); // A completed sole match MUST release Enter to submit the command. if (matches.length === 1 && matches[0] === prefix.trim()) return null; return matches.length ? matches.map(value => ({ value: `${value} `, label: value })) : null; }, ~~~ Mara types `/seeds wel`\. The completion offers the full argument text `welcome `\. When `welcome` is already the sole exact match\, returning `null` lets Enter submit rather than continually reaccepting the completion\. A completion\-array equality test is helpful\, but it is not a terminal\-key\-dispatch test\. #### Inspect progress **Observed\:** - `wel` produced `welcome `\. - `welcome` and `welcome ` produced no completion\. - The tool’s greeting matched the headless command’s greeting\. - Quiet startup produced zero startup notices\. - A headless command produced one custom message\. The supplied Seed Desk proof simulated confirmation\/notification UI\. It did not exercise actual terminal autocomplete and Enter behavior\. #### Quiet is a startup choice\, not a permission Exit the stage and restart it with the flag\. **Terminal shell—suppress the startup notice\:** ~~~sh omp --no-extensions --no-skills -e "$EXAMPLES/seed-desk/01-welcome/index.ts" --seed-quiet ~~~ This suppresses only the startup notification\. Commands and tools still work\. Register flag names without the leading `--`\; use the leading `--` in the shell\. In this parser\, a boolean flag’s presence means `true`\. Do not assume `--seed-quiet=false` means false\; omit the flag to use its false default\. #### Failure and mode boundaries - An inspect request without a topic throws an error\. - An unknown human verb produces guidance and changes nothing\. - The tool checks its `AbortSignal` before doing work\. - With UI\, the command uses `notify()`\. - Without UI\, it uses `sendMessage(..., { triggerTurn: false })`\, so the answer is not lost in an inert notification\. - Reloading code is not accomplished by directly running the TypeScript file\. Restart the explicit launch when testing an edit\. **Exercise\:** ask the agent to reserve basil through `seed_welcome`\. **Checkpoint\:** it should report that no stock\-changing operation exists\, not invent `reserve` or attempt to invoke `/seeds`\. ### Milestone\: the desk gains a real query surface The next Saturday\, Mara’s fictional desk has three seed varieties\. Repeating a prose list has become awkward\: the agent needs stable IDs\, family filters and a clear error for an invented ID\. She replaces stage 1 with stage 2\. These stages are independent\, not cumulative imports\. Files\: - [Stage 2 entry]() - [Shared catalog functions]() - [Fictional inventory]() - [Tool description]() **Terminal shell—after exiting stage 1\:** ~~~sh omp --no-extensions --no-skills -e "$EXAMPLES/seed-desk/02-catalog/index.ts" ~~~ **Human OMP slash commands\:** ~~~text /seeds query /seeds query herb /seeds inspect basil-genovese ~~~ **Model tool arguments—call `seed_catalog`\:** ~~~json {"op":"query","family":"herb"} ~~~ **Model tool arguments—call `seed_catalog`\:** ~~~json {"op":"inspect","id":"basil-genovese"} ~~~ Stage 2 supports **`query` and `inspect` only**\. It does not have a `discover` operation merely because stage 1 had one\. #### One shared domain\, two entrances This is the complete small helper used by both interfaces\. **TypeScript source—[stage 2’s `catalog.ts`]()\:** ~~~ts import fixture from "./inventory.json"; export interface Seed { id: string; name: string; family: string; packets: number; } export const inventory: readonly Seed[] = fixture; export function inspect(id: string): Seed { const seed = inventory.find(item => item.id === id); if (!seed) throw new Error("Unknown seed ID. Query the catalog for valid IDs. Nothing changed."); return seed; } export function query(family?: string): readonly Seed[] { return family ? inventory.filter(seed => seed.family === family) : inventory; } export function summary(seeds: readonly Seed[]): string { return seeds.length ? seeds.map(seed => `${seed.id}: ${seed.name}, ${seed.packets} fictional packets (${seed.family})`).join("\n") : "No fictional seeds match that family."; } ~~~ **Expected output for the herb query\:** ~~~text basil-genovese: Genovese basil, 8 fictional packets (herb) ~~~ The tool returns that summary in `content`\, and records in\: - `details.scope: "fictional-fixture"` - `details.seeds` This is better than asking the agent to scrape a notification\. The tool gives it stable targets\, while the host gets structured records\. #### Inspect progress and failure **Observed\:** the real loader\, runner and intercepted tool adapter returned only `basil-genovese` for the herb query\. Slash\/tool summaries matched\. Unknown inspection IDs threw\. A pre\-aborted call was refused through the intercepted path\. The family match is exact and case\-sensitive\. An unknown family gives an empty query result\; an unknown inspect ID is an error\. No read appends reservation state\. **Exercise\:** compare these two requests\: **Model tool arguments—call `seed_catalog`\, one request at a time\:** ~~~json {"op":"query","family":"unknown-family"} ~~~ ~~~json {"op":"inspect","id":"unknown-seed"} ~~~ **Answer\:** the query reports no matches\. The inspection fails because it promises to identify one existing target\. ### What changes next\? Mara can now ask\, “Which herbs are available\?” But the eight packets are still a static fixture\. To represent a reservation\, she needs a state model\, an ownership scope and a concurrency check—not merely another button\. That is the next chapter\. *Source\, snapshot 2026\-08\-29\: the linked Seed Desk files\; `packages/coding-agent/src/extensibility/extensions/types.ts`\, `ToolDefinition`\; `packages/coding-agent/src/extensibility/extensions/wrapper.ts`\, `RegisteredToolAdapter`\, `ExtensionToolWrapper`\.*