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

Annotations give readOnlyHint and openWorldHint, and the description adds genuine beyond-schema context: fewer fields than the full profile, the raw.html payload, the gating rationale, and the credit cost. It stops short of detailing rate limits or the exact field set, so not a 5.

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 purpose is front-loaded, but the tangent about Instagram's gating rationale and the sibling post embed on /v1/instagram/post is discursive and doesn't help the agent invoke the tool. Tighter phrasing would earn more.

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?

With no output schema, the description usefully describes the return (fields plus raw.html markup), the cost, and when to use it. The only notable gap is the undocumented cache_max_age parameter.

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 only 50%: handle is documented in the schema but cache_max_age has no description anywhere. The description adds no parameter-level detail to compensate, so the cache_max_age gap is unaddressed.

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?

Specific verb and resource: reads an Instagram profile via the public embed card and returns the embed HTML in raw.html. It clearly distinguishes itself from instagram_profile by noting it carries fewer fields and produces markup.

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?

Explicit when-to-use: reach for it when instagram_profile is blocked, or when you want the rendered markup. It also states the 1-credit cost, giving the agent a decision basis.

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