Habitica MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the tool performs an addition operation, implying a write/mutation, but doesn't disclose any behavioral traits such as permissions required, whether it's idempotent, error conditions, or what happens on success (e.g., returns the new item ID). For a mutation tool with zero annotation coverage, this is a significant gap.

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 extremely concise at just four words, front-loading the core action and target without any wasted words. Every element ('Add', 'checklist item', 'to task') earns its place by defining the tool's scope. It could benefit from more detail, but as-is, it's perfectly structured for brevity.

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 this is a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns, error handling, or behavioral nuances. While the purpose is clear, the lack of context for usage, parameters, and outcomes makes it inadequate for safe and effective use by an AI agent.

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 input schema has 100% description coverage, with both parameters ('taskId' and 'text') clearly documented in the schema. The description adds no additional meaning about parameters beyond what the schema already provides (e.g., no examples, formatting hints, or constraints). According to the rules, when schema_description_coverage is high (>80%), the baseline is 3 even with no param info in the description.

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 action ('Add') and target resource ('checklist item to task'), making the purpose immediately understandable. It distinguishes from sibling tools like 'delete_checklist_item' and 'update_checklist_item' by specifying the creation operation. However, it doesn't explicitly mention what type of checklist item is being added (e.g., to a task management system), which prevents a perfect score.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing task), when not to use it (e.g., for updating existing items), or refer to related tools like 'get_task_checklist' for context. The agent must infer usage from the tool name alone.

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