Inboxes: Add a New Agent

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

Goes beyond the annotations (which only declare non-read-only, non-destructive, non-idempotent) by disclosing the required auth mechanism (User API key via `api-access-token` header), the underlying endpoint, and that values are transmitted unchanged including Persian/Arabic-Indic digits. It does not state what happens to existing members or how failures are surfaced, but it adds real context the annotations do not.

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?

Front-loads the purpose, then layers endpoint, auth and body details compactly with no filler sentences. The bracketed '[Inboxes]' tag and the language note are slightly redundant but not wasteful.

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 mutation tool with no output schema and full schema coverage, the description supplies endpoint, auth and body requirements, which is close to sufficient. It still omits the add-vs-replace semantics relative to gapify_update_inbox_agents and any error/edge behavior, leaving a gap an agent could get wrong.

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 inbox_id, user_ids, account_id and extra_body are already documented; the description largely restates the required body fields. The one genuine addition is the note that text/ID values may be written in Persian or Arabic-Indic digits and are sent unchanged, which is a small semantic gain over the schema.

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+resource ('Add agents to an inbox') and even names the endpoint POST /inbox_members, so the action is unambiguous. It does not, however, distinguish itself from close siblings like gapify_update_inbox_agents (which also mutates inbox membership) or gapify_remove_inbox_agent.

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?

No explicit when-to-use or when-not-to-use guidance. The agent must infer that this is for adding members while gapify_update_inbox_agents replaces the membership set and gapify_remove_inbox_agent removes members; the description never says so, leaving the add-vs-update choice to guesswork.

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