update_habit

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

With no annotations, the description should disclose behavior. It explains habit_id resolution and that omitted fields are untouched, but does not mention error handling, permission requirements, or whether fields are truly mutable. The mention of v0.2 optional fields adds some context but leaves other behavioral aspects unclear.

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?

The description is concise with no extraneous text. The first sentence communicates the purpose, followed by focused details on habit_id and optional fields. Every line adds value, and the structure is front-loaded and easy to scan.

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?

Given 6 parameters, no annotations, and an output schema not shown, the description is incomplete. It omits explanations for key mutable fields like recurrence, labels, and null behavior. The mention of v0.2 fields not in schema creates confusion. Overall, it fails to fully equip an agent for correct invocation.

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 0%, so the description must add meaning. It thoroughly details habit_id formats and two extra fields (deadline_time_of_day, subtask_template) not in schema, but the 5 other schema parameters (title, description, etc.) receive no description. This partial coverage leaves most parameters semantically opaque.

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?

The description clearly states the tool patches mutable fields on a habit, with the first sentence specifying the operation and resource. It distinguishes from siblings like create_habit and delete_habit by explicitly focusing on updating existing habits, leaving no ambiguity.

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?

The description implies use for partial updates via 'Omitted fields stay untouched' but provides no explicit when-to-use or when-not-to-use guidance relative to alternatives like update_habit vs mark_habit_occurrence. Context of sibling tools suggests this is for field updates, but the description lacks direct contrast.

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