x_api_get_direct_messages_events_by_id

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

With no annotations, the description carries the full burden and excels: it discloses read-only risk, required OAuth scopes, environment-selection behavior for scopeTenantId/scopeUserId/scopeAccountId/credentialKey, common failure conditions, and safety warnings about sensitive data. This is far beyond basic expectations.

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 lengthy but well-organized into labeled sections, making it easy to scan. Minor redundancy exists ('Get DM event by ID' repeated in Use when, read-only repeated), but every section adds useful context for a tool with no annotations.

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?

The description includes expected response shape, common failure conditions, prerequisites, and auth behavior, which is strong given no output schema and no annotations. It does not explain the semantics of returned event data or detail all optional parameters, but it provides adequate context for correct invocation.

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 0% and 7 params exist. The description explains event_id as required path and gives behavior context for scopeTenantId, scopeUserId/scopeAccountId, and credentialKey in the environment-selection section, but it does not explain authorizationKey or preferredAuthType beyond the schema enum. Partial compensation for low coverage.

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 'Get DM event by ID' clearly states the verb and resource, and the 'by ID' qualifier distinguishes it from sibling tools that fetch events by conversation, participant, or list. This directly clarifies the tool's scope.

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 includes a 'Do not use when' clause for exploration/auth scenarios and recommends x_schema_discovery or x_query_suggestion. However, the 'Use when' clause merely restates the purpose and does not mention alternative sibling tools for fetching DM events by conversation/participant, leaving comparative guidance incomplete.

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