Publish Text Thread

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

The description discloses a key behavioral trait: the two-step flow (creates a container, then publishes it). This is beyond the annotations, which are minimal (readOnlyHint=false, etc.) and don't reveal this internal process. It also states the return value (Media ID). While it doesn't mention potential intermediate states or failure handling, the two-step disclosure is valuable and adds context beyond 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 compact and well-structured: a two-sentence overview, an Args list, and a Returns line. It front-loads the core purpose but repeats some parameter details already in the schema (e.g., text length). Still, it is efficient and scannable, earning a 4 rather than a 5 due to slight redundancy.

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 publish operation with seven parameters, this description is fairly complete: it explains the two-step process that involves a container creation, a crucial detail for understanding the API call pattern, and describes the return value. It does not cover all parameters (though schema handles them) nor error handling, but it hits the key points for invoking the tool correctly. The presence of the two-step flow and return type makes it complete enough for an agent to act.

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 86%, so the baseline is 3. The description lists only 4 of 7 parameters and adds little beyond what the schema already provides (e.g., text max length matches schema). It omits location_id, reply_control, and response_format, but the schema describes those well. The description does not compensate for the missing 14% coverage, so it stays at baseline.

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 action 'Publishes a text-only post to Threads' – a specific verb and resource that distinguishes it from sibling publishing tools (image, video, carousel, gif, link) by explicitly saying 'text-only'. This makes the tool's intent unambiguous without needing to open the 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?

The description implies usage for text-only posts but does not explicitly mention alternatives or when to choose this over sibling publishing tools. An agent could infer from the name and siblings, but there is no direct guidance like 'for images use threads_publish_image'. It provides context but no exclusions or comparisons.

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