Publish an image post

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

Annotations already declare the mutation profile (readOnlyHint=false, idempotentHint=false, openWorldHint=true), so the safety bar is largely covered. The description adds a genuine non-structured behavior: the IG_ENABLE_WRITES environment gate that must be satisfied before any call succeeds. It omits other operational traits such as publish rate limits (see sibling ig_publishing_limit) and the asynchronous container-processing flow.

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?

Two short sentences, zero filler, with the capability statement front-loaded and the blocking precondition immediately after. Every clause carries information an agent needs.

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?

No output schema exists, so the description could carry more, yet it never explains the return behavior (the pending container_id referenced only inside the wait_seconds schema text) or how this relates to ig_publish_container / ig_get_container_status. For a write tool with a container-based async pipeline and a sibling rate-limit tool, this is adequate but leaves notable gaps.

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%, so all four parameters (image_url, caption, alt_text, wait_seconds) are already documented in the schema with types, bounds and formats. The description adds no syntax, format or default information beyond that, so the 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 (publishes) and resource (single-image feed post) with a binding constraint (public JPEG URL). The 'single-image feed post' scoping implicitly separates it from the sibling publish tools (ig_publish_reel, ig_publish_story, ig_publish_carousel) without the agent needing to open a 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?

It gives a hard precondition (IG_ENABLE_WRITES=true) and an implicit content-type constraint via 'single-image feed post', which is real routing value. However, it never names an alternative or states when-not-to-use it (e.g. multiple images → ig_publish_carousel), so usage remains implied rather than explicit.

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