ygo_compare_decks

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

With no annotations supplied, the description carries the full burden and does disclose output structure (section-by-section breakdown, shared/only-A/only-B, copy-count deltas, overlap percentage) and tolerated input shapes. It is silent on whether it mutates state, performs legality checks, or how the overlap percentage is weighted (card names vs copies), which matters for interpreting results.

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 imperative trigger, then the mechanism and output, then the anti-hallucination directive. No filler and every sentence carries distinct information.

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 2-parameter, no-output-schema, no-annotation tool, the description adequately covers inputs, comparison dimensions and return shape. The remaining gap is that the exact semantics of the reported overlap percentage and copy-count differences are left implicit, which an agent would need to interpret the results correctly.

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% and both parameters already document the accepted forms, so the description's mention of .ydk paths, raw text, ydke:// links and DeckData largely restates the schema. It adds no per-parameter nuance (e.g. precedence when both a path and raw text are passed), so baseline 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?

States a specific verb and resource ("Compares two decks") and enumerates the exact scope (Main/Extra/Side) plus the return contents (shared cards, A-only, B-only, copy-count differences, overlap percentage). This is clearly distinguishable from siblings like ygo_parse_deck (single deck) and ygo_compare_monthly_meta (meta trends) without opening a 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?

Gives concrete trigger phrasings ("what do these two lists share", "core vs tech", comparing a community deck to your own) plus an explicit directive to call the tool rather than answer from memory. It does not name the adjacent alternatives an agent might wrongly pick (e.g. ygo_parse_deck for one deck, ygo_optimize_deck for improvement advice), so the routing guidance is strong but not exhaustive.

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