getThread

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

Annotations already declare read-only, idempotent, non-destructive, but the description adds substantial substance beyond them: cards come back without bodies, ordered oldest first with undated last, only locally indexed messages appear, messages are linked by Message-ID/In-Reply-To/References rather than subject or participants, and recognized duplicates are collapsed into a copies field with totals counting groups.

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 tight paragraphs, front-loaded with the scope and ordering before the follow-up instructions. Nearly every sentence carries load, though the trailing clause 'total and paging count groups' is terse enough to be slightly opaque.

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?

An output schema exists, so return shape needn't be spelled out, yet the description still covers the semantics an agent needs: body-less cards, ordering, duplicate collapsing, and header-based threading. Combined with annotations covering the safety profile, nothing needed to call it correctly is absent.

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% and already documents key, limit range and cap, and the offset/nextOffset continuation protocol, so the baseline applies. The description reinforces that the 'key' is a card key from the returned list rather than a Message-ID header, but adds no new syntax or constraints beyond 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 and resource — 'List the locally indexed conversation containing a message, across all folders of one connection' — which cannot be confused with listMessages or search. It also distinguishes itself from getMessage by positioning that sibling as the follow-up for reading bodies.

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?

Explicitly routes the agent: use this to enumerate the conversation, then call getMessage with the same connection and each card's key. It gives a paging stopping rule ('Stop when there is no nextOffset'). What's missing is an explicit statement of when NOT to use it (e.g., a single-message read or a subject-based grouping), though the linking-by-headers note implies the latter.

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