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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds real behavioral detail beyond that: the rendered layout (weekday initials, weekend shading, grey unscheduled boxes, Done column), page-count limits, and a return summary of month facts, per-habit scheduled day counts, preview and PDF link. It loses a point only because the return-value recap is partly redundant with the existing output schema.

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 trigger condition and the pre-processing instruction are front-loaded, and the layout description is dense but informative. The quoted trigger-phrase list and the feature inventory (28 languages, shading, week lines) run long, though each element does convey buildable detail rather than 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?

With 13 optional parameters and no required fields, an agent needs to know defaults, ranges, and when to omit arguments — the description plus schema covers all of this, and an output schema exists so return values need not be fully explained. Nothing needed to invoke the tool correctly is missing.

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 description coverage is 100%, so every one of the 13 parameters is already documented in the schema, which sets the baseline at 3. The description reinforces a few semantics — per-habit weekday limits rendering grey boxes, one-page-per-month, Letter/A4 and orientation options — but adds little syntax or format guidance the schema does not already carry.

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 opens with a specific verb-and-resource pairing (generating a printable habit tracker) and enumerates the exact user phrasings that trigger it. It also states what the output artifact is — a PDF grid with one row per habit and one box per day — so an agent knows precisely what the tool produces without opening the schema.

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?

It gives an explicit when-to-use clause with five quoted trigger phrases, plus a pre-call instruction for handling pasted or uploaded habit lists (convert to the habits list first). It closes with explicit when-not-to-use exclusions: no reminders, no tick storage, no habit-app sync.

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