Harness spec 1.2.0: the library's tools fit both projects; the CLI implements it

The CLI's facts in memory, notes_search, note_manage, skills_list,
skill_view and skill_manage are `variables` now, filled with the CLI's own
values (src/tool/spec-vars.ts): every description and parameter list the CLI
sends is word for word what 1.1.0 said, except note and document ids, which
are strings on both sides (a number is still taken). Descriptions are
filled by the prompt texts' rules, parameter descriptions too. `narrow`
says what a project offers of a shared tool's parameters. Memory's changes
are one pure function (applyOps). Conformance: fill, narrow, memory.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/tool/tool.ts

@@ -4,7 +4,7 @@ import { z } from "zod"
 import type { PermissionRequest } from "../permission/evaluate.ts"
 import { expandHome } from "../config/paths.ts"
 import type { ToolSpec } from "../provider/types.ts"
-import { PURPOSE_DEF, TOOL_SPECS } from "../harness.ts"
+import { fillParameters, PURPOSE_DEF, TOOL_SPECS } from "../harness.ts"
 
 export interface ToolContext {
   /** Absolute project root. */
@@ -91,6 +91,9 @@ export interface Tool<S extends z.ZodType = z.ZodType> {
   schema: S
   /** The JSON Schema sent to the model, when it does not come from `schema` (MCP tools). */
   jsonSchema?: Record<string, unknown>
+  /** The values of the spec's `{{variables}}` for this tool: its description is filled with them
+   *  already (described), its parameters' descriptions when it is sent (toSpec). */
+  vars?: Record<string, string>
   /** Where the model says what a call is for, shown when the user is asked to allow it: the
    *  `purpose` argument added to every tool (the default), a field of the tool's own (bash's
    *  `description`), or false for a tool that never asks. */
@@ -134,7 +137,7 @@ export function toSpec(t: Tool): ToolSpec {
   if (t.jsonSchema) schema = t.jsonSchema
   // A built-in tool's parameters are the harness spec's, as LLeMbas sends them too; its zod schema
   // validates the call, and tests/harness.test.ts keeps the two the same shape.
-  else if (TOOL_SPECS[t.name]) schema = structuredClone(TOOL_SPECS[t.name]!.parameters)
+  else if (TOOL_SPECS[t.name]) schema = t.vars ? fillParameters(TOOL_SPECS[t.name]!.parameters, t.vars) : structuredClone(TOOL_SPECS[t.name]!.parameters)
   else {
     schema = z.toJSONSchema(t.schema, { target: "draft-7", io: "input" }) as Record<string, unknown>
     delete schema.$schema