slack_read_thread

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

Annotations only declare readOnlyHint and openWorldHint, so the description carries real weight here: it discloses pagination semantics ('Returns complete=false while more remain'), the max_pages default and its stop condition, and the exact OAuth scopes required. It does not cover rate limits or ordering of returned messages, but the added context is substantial.

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 short clauses, no filler, and the pagination/default information is front-loaded where an agent will read it. Slightly dense with semicolons, but every clause carries information.

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 values needn't be spelled out, though the description usefully explains the complete flag anyway. For a 10-parameter paginated read with 0% schema coverage, a few parameters (inclusive, limit) remain unexplained, keeping it just short of complete.

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 0% across 10 parameters, so the description must compensate. It meaningfully explains cursor, latest/oldest bounds, all_pages and max_pages, but leaves limit, inclusive, thread_ts, workspace and channel_id (including how to obtain a thread_ts) entirely undocumented.

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 ('Read thread pages') and scopes it with cursor and timestamp bounds, which distinguishes it from slack_read_channel (channel-level) and slack_search_messages. It does not name a sibling alternative explicitly, but the thread-vs-channel distinction is clear from the resource named.

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 implies when to use it (when you need a thread's replies, possibly paginated), and gives some operational guidance ('all_pages stops at max_pages'), but never says when to choose this over slack_read_channel or slack_search_messages, nor any prerequisites for obtaining thread_ts.

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