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

Beyond the annotations (destructiveHint=true, readOnlyHint=false), the description discloses that the merge can overwrite current entity values, may incur LLM cost, can fall back to rules on arbiter failure, and advises inspecting database warnings and the actual fusion method. This is rich, honest behavioral disclosure.

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?

The description is compact yet information-dense. Every sentence contributes: purpose, arbitration modes, return contents, destructive side effects, fallback behavior, usage guidance, and a docs reference. It is front-loaded with the core purpose and avoids redundancy.

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?

The description covers prerequisites, exclusions, cost, failure modes, side effects, and return value categories. Since an output schema exists, detailed return structure is not required. For a destructive, potentially costly merge operation, this is complete enough for an agent to invoke it 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%, so the baseline is 3. The description adds meaningful context for arbitration_model by explaining rule-based behavior and LLM cost implications, and clarifies that result_ids must refer to the same entity. This goes beyond the schema's bare parameter descriptions.

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 action ('Fuse two or more records of the same entity') and a clear resource ('records' into a 'new arbitration record'). It also distinguishes itself by emphasizing same-entity merging, which separates it from sibling tools like merge_semantic_concepts.

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 usage context: use after separately recovered model runs, not for merging different entities. It also explains when rule-based vs LLM arbitration applies. However, it does not name alternative sibling tools or explicitly say when not to use them, so it stops short of a 5.

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