add_competitor

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

Beyond the annotations (readOnly=false, idempotent=false, destructive=false), the description discloses the key side effect — the first snapshot is taken immediately — and enumerates three distinct error outcomes with their conditions (invalid_param, plan_limit_reached, conflict on already-tracked accounts). That is exactly the mutation context an agent needs before committing.

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?

Four compact sentences, front-loaded with purpose followed by preconditions and error semantics. No repetition of the title, no filler, and each sentence carries actionable information.

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 one-parameter mutation with no output schema, the description covers purpose, mechanism, preconditions, side effects, and all known failure modes. Nothing an agent needs in order to call this correctly is missing.

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% with a single parameter, so the schema already documents the handle format, the @ prefix tolerance, and the public-business-account requirement. The description reinforces the account-type constraint but adds no new syntax or formatting detail beyond what is structured. 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 and resource ('Track a competitor'), plus the mechanism ('Looks the handle up through Meta and starts tracking it'). This clearly separates it from siblings like list_competitors, get_competitor, and remove_competitor without requiring the agent to open any schema.

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?

Gives explicit preconditions and exclusions: the account must be a public Instagram business or creator account, and personal/private accounts cannot be read. It also maps failure modes (422, 403, 409) to causes, which tells the agent when the call will fail. It stops short of naming alternative tools for listing or removing competitors, so not a full 5.

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