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

Annotations already cover the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the description only needs to add behavioral context beyond that. It adds useful details: the decoded output contents and the single-code scope, and explicitly warns against passing multi-hero team blobs. This goes beyond the annotations without contradicting them.

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 with zero filler: the first states purpose and outputs, the second adds input tolerance, and the third routes to the correct sibling tool. The most important scoping constraint is placed at the end but is clearly emphasized, and every sentence contributes to correct invocation.

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 the presence of an output schema, the description does not need to enumerate return fields. It covers the input format, scope limitations, and output categories, and it references the correct alternative tool for the multi-hero case. This is complete for a single-parameter read-only decoding 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 schema already documents the single 'code' parameter at 100% coverage with a basic description, so the baseline is 3. The tool description adds meaningful value by providing a concrete example, explaining that whitespace/line wraps are tolerated, and clarifying that the code must be a SINGLE build code rather than a multi-hero blob. This materially improves parameter understanding.

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 ('Decode'), a specific resource ('in-game GW1 skill template code'), and enumerates the exact outputs: professions, attribute allocations, and the 8 skills with stats and descriptions. It also distinguishes itself from the sibling tool decode_pawned_team by explicitly limiting scope to a SINGLE build code, so an agent can clearly tell which tool to pick.

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 explicit when-to-use guidance: use for a single build code, and use decode_pawned_team for a multi-hero pawned-n2 team blob. It also provides a practical input-handling note that whitespace and line wraps are tolerated, which helps the agent pass user pasted code without pre-cleaning.

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