update_relation

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

No annotations are provided, so the description carries the full burden. It explicitly discloses append vs. overwrite behavior for each field (likes/dislikes/important are appended; feeling/closeness/notes overwritten) and enumerates valid target_id values. This goes beyond simple parameter naming, though it does not mention error cases, idempotency, or return values.

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 a compact bulleted list of parameters with concise Japanese explanations. Every line provides necessary information; no filler or redundancy. It is front-loaded with the purpose statement, making it easy to scan.

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 7-parameter mutation tool with no annotations, the description covers the main behavior well, including append/overwrite distinctions and target_id scope. However, it does not specify what happens if the target does not exist (whether it creates or errors), and omits output/error behavior, though an output schema exists. Overall, nearly complete.

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 0%, so the description must compensate. It explains every parameter: target_id's allowed values, that likes/dislikes/important are lists that get appended, feeling/closeness/notes are overwritten, and closeness range (0.0–1.0). This adds meaningful semantics absent from the schema.

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 clearly states 'Update relationship information for a specific target' (特定の相手...への関係性情報を更新する), naming the verb (update), resource (relationship info), and target scope. It distinguishes itself from siblings: get_relations (read) and clear_relation_field (field-specific clearing) by focusing on full updates with append/overwrite semantics.

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 clarifies when to use the tool: to update relationship info for self, owner, or other character IDs. It implicitly differentiates from siblings (get_relations is read, clear_relation_field is field clearing) but does not explicitly state exclusions or when to prefer an alternative. Context is clear enough for an agent.

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