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

Beyond the readOnlyHint annotation, the description discloses key behavioral traits: it 'only uses logical techniques — never guesses' and that steps will 'end before completion' if the puzzle cannot be solved logically. It also explains the response includes every solving step, a technique summary, and a solve_url, giving the agent a clear model of call behavior.

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 organized into short labeled sections and front-loads the primary purpose before input and return details. It loses a point for minor redundancy: 'tutorial links' appears in the returns list and is then restated as 'tutorial_links' in the final sentence.

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 a single parameter and no output schema, the description supplies all essential context: exact input format, return contents, logical-only behavior, early termination condition, and an explicit use case. It also mentions the interactive solve_url and tutorial links, which are valuable for an agent deciding to invoke the tool.

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 only parameter, puzzle, is already fully documented in the schema (81-character string, 0 or ., whitespace ignored), so the description merely repeats schema content. With 100% schema description coverage, the baseline of 3 is appropriate; the description adds no significant parameter meaning beyond what the schema already provides.

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 ('solve') and resource ('a sudoku puzzle'), and specifies the manner: 'completely with step-by-step logical deduction.' It also states when to use it — 'when the user wants to understand how to solve a puzzle from scratch' — helping differentiate it from sibling tools like explain_next_step or get_sudoku_puzzle.

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 explicitly names its intended use case: 'Use this when the user wants to understand how to solve a puzzle from scratch.' However, it does not state when not to use it or explicitly mention alternatives such as explain_next_step for a single step or check_progress for tracking existing progress, so it falls slightly short of full alternative routing.

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