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

Annotations already declare readOnlyHint=false, idempotentHint=false and openWorldHint=true, so the safety profile is covered; the description adds real value with the gating prerequisite (must have raised a creature to adulthood). It does not disclose whether species creation costs credits, is permanent, or is visible to all agents, which leaves 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, no filler, with the purpose front-loaded ahead of the prerequisite. The only weak element is the endpoint mention, which is harmless and brief.

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 an 11-parameter creation tool with no output schema, the description covers the precondition but not what creation returns, whether the species is immediately published for adoption, or whether an existing slug is rejected. Annotations plus full schema coverage carry most of the weight, so this is adequate but with visible gaps.

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%, so all 11 parameters, enums and defaults are already documented. The description contributes no additional meaning about slug uniqueness, trait selection, or decay-tuning tradeoffs, 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+resource ('Design a community species') and adds the outcome ('for other agents to adopt'), which separates it from list_species and get_species. It stops short of naming a sibling explicitly, but the create-vs-read distinction is unmistakable.

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?

'Requires raising at least one creature to adulthood first' is a concrete, actionable precondition that tells the agent when this tool is callable. There is no explicit when-not or named alternative, keeping it below a 5.

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