log_habit

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the action but doesn't mention side effects like idempotency, overwriting previous logs, or the special behavior for pullup_gtg requiring rep counts. For a mutation tool, 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 a single, front-loaded sentence with no filler, achieving maximum efficiency. However, it omits important behavioral details that could be incorporated without much length, so it's concise but slightly under-specified.

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?

This simple 2-param tool has no annotations and relies on the description for context. The description fails to address idempotency, validation errors, or the conditional nature of pullup_reps, rendering it incomplete for a safe mutation operation.

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 100%: both parameters have detailed descriptions, including enum-like values for habit_name and conditional use for pullup_reps. The tool description adds no semantic value beyond restating 'habit', so the baseline of 3 is appropriate.

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 uses a specific verb ('Mark') and resource ('habit as completed for today'), making the tool's core function immediately clear. It also distinguishes itself from the sibling read-only tools (get_today_status, get_streak, get_mission_overview) which are all queries.

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?

No guidance is given on when to use this tool vs alternatives, nor any context about habit validation, prerequisites, or when not to log. The sibling names imply read-only tools, but the description doesn't explicitly exclude or compare, leaving usage to inference.

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