create_habit

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine semantic context — that the goal link is optional and that minimum_version exists as a fallback 'for bad days' — but says nothing about what happens with duplicate titles, where the habit is stored, or what a successful creation returns.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single sentence, front-loaded with the verb and resource, where every clause (optional goal link, cue, minimum version) maps to a distinct parameter and earns its place. No filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 6-parameter creation tool with no output schema and thin schema descriptions, the definition conveys the concept but not the outcome — an agent doesn't know whether it receives a habit ID, whether the created habit is immediately listed by list_habits, or what failures look like. Adequate but leaves operational gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is only 17% (just the frequency format), so the description must carry the load, and it meaningfully does: it tags goal as optional, explains cue, and gives purpose to minimum_version that a bare name would not convey. Title and description remain self-evident; only frequency's format lives in the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Create a repeatable habit') plus the notable modifiers (goal link, cue, minimum version). An agent can distinguish it from create_goal and log_habit without opening the schema, though the description never explicitly contrasts itself with those siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied: 'repeatable' signals this defines a habit template rather than recording an occurrence, which nudges an agent away from log_habit, and 'optionally linked to a goal' hints at the relationship with create_goal. There is no explicit when-to-use, no prerequisites, and no named alternative.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.