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

Annotations already declare destructiveHint=true and idempotentHint=false, so the description's warning about no deletion adds context beyond the annotations. It also discloses that `id` is immutable ('not changeable later'), which is a behavioral constraint not present in the schema. Minor gap: it doesn't state whether creation is idempotent or what happens on duplicate tag, but the annotation covers idempotency.

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, each with a distinct purpose: the action, the critical `id` constraint, and the deletion warning. No filler or repetition of schema details. Front-loaded with the primary action.

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 create tool with 6 parameters and no output schema, the description covers the key behavioral constraints (unique immutable id, no deletion) and points to the sibling for tag checking. It doesn't explain the return value, but no output schema exists and the annotations cover safety. The only minor gap is not mentioning that `applicationId` comes from list_applications, though the schema already says that.

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%, so the baseline is 3. The description adds value by explaining that `id` is a Bridge SDK tag, unique within the game, and not changeable later — this is semantic context beyond the schema's 'tag' description. It also clarifies the deletion limitation, which helps the agent understand the lifecycle of the `id` parameter.

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 ('Add') and resource ('a leaderboard to a game'), and clarifies the `id` field's role as a Bridge SDK tag. It distinguishes itself from sibling tools like list_leaderboards and update_leaderboard by noting deletion is unavailable and tags must be checked first.

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 tells the agent to check list_leaderboards for existing tags before creating, and warns that deleting a leaderboard is not available. This gives clear when-to-use guidance and an important exclusion, which is strong for a create tool.

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