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

With no annotations, the description carries the burden and does much of it: it discloses the return payload (FEN, full solution as UCI moves, player rating), the UCI notation with a worked example ("c2h7" for Qxh7#), and the UTC day semantics. It omits edge behavior such as what happens for a future or invalid day, or whether every date has a puzzle.

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?

Three sentences, front-loaded with the core action and scoping, then return shape, then use cases. Slight redundancy in restating that the FEN gives the side to move, but nothing wasteful.

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 single-optional-parameter read tool with no output schema and no annotations, the description covers everything an agent needs: what it fetches, the date constraint, and a precise inventory of returned fields including move notation format.

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% and the single `day` parameter is already documented with its pattern and an example. The description's 'past UTC day' phrasing reinforces but does not materially extend the schema's 'Optional past UTC day to fetch instead of today's puzzle'.

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?

States a specific verb and resource ('Get the ChessVox daily puzzle') and immediately scopes it to today or a past UTC day. The resource is distinct enough from the sibling tools (mate rush puzzles, starter repertoires) that an agent can tell them apart without opening schemas.

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?

Gives concrete usage contexts — showing a puzzle, hinting the first solution move, verifying a user's answer — which map well to how an agent would pick this tool. It stops short of naming when NOT to use it or pointing at the sibling puzzle tools as alternatives.

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

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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses batch size, rating range, source pool, and that each puzzle includes a FEN and UCI winning move. However, it does not state whether batches are random or repeatable, how the 600–1800 rating range is sampled, or any rate-limit/caching behavior, leaving meaningful gaps for an unannotated tool.

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 tightly structured and front-loaded with the core action and scope. Every sentence adds relevant information: source pool, rating range, returned fields, and typical use. There is no filler or repetition.

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 zero-parameter retrieval tool with no output schema and no annotations, the description supplies the essential context: batch size, rating range, source, and the shape of each puzzle. It is nearly complete, though additional notes on randomization, repetition, or exact return structure would make it fully self-contained.

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 has zero input parameters, so parameter semantics are inherently simple and the baseline is 4. There are no parameters for the description to explain, and the schema is complete for a no-argument call.

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 states a specific verb and resource: get a batch of 20 mate-in-1 training puzzles from the ChessVox Brain Arcade pool. It clearly identifies the puzzle type, batch size, rating range, and returned fields. Sibling tools are not explicitly mentioned, so it falls just short of full sibling differentiation.

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 gives clear intended use cases: quick tactic drills or generating practice positions. It does not explicitly contrast this tool with chessvox_daily_puzzle or chessvox_starter_repertoires, and it provides no when-not-to-use guidance. Still, the usage context is clear enough for an agent to select it appropriately.

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

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

With no annotations, the description carries the full burden. It discloses that entries are free, ChessVox-authored, and that each has color, description, style tags, line count, and UCI preview moves — useful read-only context. However, it does not state pagination, ordering, or whether any auth/quota applies, leaving some behavioral gaps.

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?

Three short sentences, front-loaded with the resource and scope, followed by the per-entry field summary and the usage hint. Nothing is redundant or padded.

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?

There is no output schema, so the description must convey return structure — and it does, listing the five fields per entry. Missing only secondary details such as list size, ordering, or pagination, which are minor for a zero-parameter listing 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 tool takes zero parameters, so there are no parameter semantics to explain and the baseline is 4. The description correctly implies a no-argument call by describing a fixed catalogue rather than any filtering inputs.

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?

States a specific verb and resource: 'List the free ChessVox-authored starter opening repertoires', with concrete examples (Italian Game, Caro-Kann) and a link. It is unmistakably distinct from the puzzle siblings (daily_puzzle, mate_rush_puzzles), so no ambiguity for selection.

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?

Explicitly names two use cases: recommending a first repertoire and previewing what a specific opening looks like move by move. It gives clear when-to-use guidance but no exclusions or named alternatives, and the sibling puzzle tools are not addressed as alternatives.

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