slack_get_channel_history

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

Annotations already carry the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the description's burden is lower. It adds useful context by explaining that effect must be set to "read" and that Spring verifies it, plus clarification of approval_ref as write-resume context. It does not contradict annotations, but it omits behavioral details like pagination or rate-limit behavior.

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?

A crisp one-sentence summary is front-loaded, followed by a compact line-per-parameter list with no filler. Each argument line earns its place, though the platform plumbing fields (project_id, project_ref, idempotency_key) could arguably be grouped, so it is efficient but not maximally tight.

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-value documentation is not the description's job. For a read-only fetch tool the description covers purpose and all parameters, but it lacks the usage-differentiation guidance needed among many Slack siblings and does not mention cursor/pagination semantics for fetching larger histories. Adequate, with clear gaps.

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?

With 0% schema description coverage, the Args section compensates by giving every one of the 9 parameters some semantic hint, including Slack ts format for oldest and purpose notes for the platform-level fields. However, it labels channel as "required" while the schema marks only effect as required and channel as nullable with a null default — a misleading discrepancy that could cause an agent to pass a required argument erroneously.

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 opening sentence "Fetch recent messages from a Slack channel" uses a specific verb and resource, clearly identifying the operation as a channel history read. It is distinct from most siblings by action, though it does not explicitly contrast with closely related tools like slack_get_thread_replies or slack_search_messages, so the differentiation is implicit rather than stated.

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 guidance is given on when to use this tool versus alternatives. With a large sibling cluster of Slack tools (slack_get_thread_replies, slack_search_messages, slack_list_channels, coding_watch_slack), an agent receives no help choosing among them; the description only states what the tool does, not when it is the right choice or when to pick another.

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