ygo_render_deck_image

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

With no annotations present, the description carries the full load and does well: it discloses that the output is attached to the result as an image block, that an absolute outputPath is returned, and where the file must be surfaced (preview tab if supported). It leaves out error behavior for malformed .ydk/ydke input and whether an existing file at outputPath is overwritten.

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?

Front-loaded with the trigger and the action before the result-handling detail, and every sentence earns its place: layout spec, return shape, host-instruction, and an anti-hallucination rule. No filler or restatement of the tool name.

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?

No output schema exists, and the description compensates by explaining exactly what comes back (image block plus absolute path) and what the agent should do with it. For a render tool with fully described parameters this is nearly complete; only failure modes and overwrite behavior are unaddressed.

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% — each of lang, input, title and outputPath is already documented in the schema, including the four accepted input formats. The description adds no parameter-level meaning beyond that (no notes on relative vs absolute outputPath, or default lang behavior), so the baseline 3 applies.

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 ('Render the deck (Main, Extra, Side) as a PNG') plus the exact layout semantics — 10 cards per row, Monster -> Spell -> Trap ordering, banned cards flagged. That combination distinguishes it in practice from the export/PDF siblings such as ygo_export_deck and ygo_generate_tournament_decklist_pdf, which produce different artifacts.

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?

'USE THIS after building or editing a deck when the user wants to see it' gives a clear trigger condition and a workflow position, and the closing line forbids re-describing the image from memory. It does not name a mutually exclusive alternative (e.g. 'for a printable PDF use ygo_generate_tournament_decklist_pdf'), so the when-not half of the guidance is missing.

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