discord_read_dm

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

With no annotations, the description carries the full behavioral burden and does so well: it discloses the ordering (oldest-first), the return fields, pagination via hasMore/nextBefore/before, and the side effect that opening the conversation may mark it as read. This is especially valuable for an operation that appears read-only but has a potential state-changing effect.

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?

Three sentences with no filler: the first states the action and key constraint, the second covers return format and pagination, the third notes the side effect. Every sentence carries necessary information and the most important usage constraint is front-loaded.

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?

Despite having no output schema, the description specifies exactly what the response contains, the message ordering, how to page, and the read-state side effect. It also tells the agent where to obtain channel_id/name (discord_list_dms). This is sufficient for correct invocation and interpretation of results.

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%, so the baseline is 3. The description adds value beyond the schema by establishing that channel_id and name are mutually exclusive, that channel_id is preferred, and that 'before' should use nextBefore from the previous response. These are semantics an agent could not derive from the schema alone.

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 action ('Reads the most recent messages') and resource ('a direct conversation'), and distinguishes itself from siblings by scoping to DMs and referencing discord_list_dms as the source of identifiers. The naming and description together make it clear this is not for guild channels or status operations.

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?

Clearly explains the two identifier options, marks channel_id as preferred, and mandates exactly one of the two — important routing guidance. It does not explicitly contrast with discord_catch_up or state when not to use this tool, but the scope is clear enough for an agent to infer the relevant case.

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