instagram_find_person

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint. The description adds valuable behavioral context beyond that: it searches existing conversations preferentially, returns a thread_id only if a conversation exists (null otherwise), and includes has_conversation and is_group flags. It also specifies the result fields, which helps the agent understand what to expect. No contradiction with annotations.

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 moderately concise, with a clear introductory sentence, then a usage note, then structured Args and Returns sections. It front-loads the core purpose and usage condition. The Returns section provides useful detail without being verbose. It could be slightly tighter by removing the Args repetition, but overall it is well-organized and efficient.

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 tool is fairly simple (2 params, output schema present) and the description covers the essential aspects: when to use, what it returns, and how the results relate to messaging (thread_id). It does not mention rate limits or authentication, but annotations already cover the read-only, idempotent nature. The only minor gap is that it doesn't explicitly state that the query can be a partial name (only in the schema), but the schema covers that. Overall, complete enough for an agent to invoke 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 description coverage is 100%, and both parameters have detailed descriptions in the schema (e.g., query includes examples and 'Partial names work', limit has min/max). The description's Args section merely restates the parameter names without adding additional meaning or nuance. Since the schema fully covers semantics, a baseline score of 3 is appropriate; the description adds no extra semantic value.

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 the purpose: finding a person to message, prioritizing existing conversations. It distinguishes this from general user search by emphasizing the messaging context and the thread_id return for existing conversations. The phrase 'searching your existing conversations before all of Instagram' and the explicit reference to passing thread_id to instagram_prepare_dm make the tool's role unambiguous.

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 conditions: use when a person is referred to by first name only or when unsure which account is meant. It implies that for exact handles or when certain, a different search (like instagram_search_users) would be more appropriate, though it does not name the alternative explicitly. The ranking behavior (existing conversations first) is also explained, which guides when to rely on this tool.

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