list_habits

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

No annotations are supplied, so the description must carry the behavioral burden. '列出' (list) implies a read-only, non-mutating operation and the text usefully discloses the shape of the returned data (current count, target, whether today's goal is met), but it says nothing about ordering, completeness guarantees, or what happens with zero habits — modest but real disclosure for a zero-parameter read.

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?

One short sentence with the action front-loaded and the returned fields appended as a compact qualifier. Nothing is redundant and nothing could be removed without losing information.

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 simple zero-parameter list tool with no output schema, the description covers what it returns (current_count, target_count, today's completion), which is exactly the information an agent needs to decide whether this call answers its question. Only the lack of any routing hint toward sibling tools keeps it from being fully complete.

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?

The tool takes no parameters, so the schema has nothing to explain and there is no semantic gap for the description to fill. Baseline 4 applies; the description adds field names as a bonus rather than compensating for any missing parameter documentation.

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 gives a specific verb+resource ('列出全部习惯' - list all habits) and even names the key fields returned (current_count, target_count, today's completion). It is clear what the tool does, but it never distinguishes itself from sibling tools such as list_todos or list_countdowns, so an agent gets no help choosing among the list_* family.

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?

There is no when-to-use or when-not-to-use guidance, and no alternative is named. The word '全部' (all) hints that no filtering is possible, but nothing tells an agent whether to call this versus today_summary or check_habit when it wants habit status.

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