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

No annotations are provided, so the description carries the full behavioral burden, and it does disclose useful traits: results are ordered by category, active threads are included, and forum channels are empty of messages. It says nothing about permissions, pagination, or whether archived/hidden channels are excluded, which leaves real gaps for a zero-annotation tool.

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 lines, front-loaded with what the tool returns, followed by the parameter note and the one edge case that matters. No filler or redundancy.

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 need no explanation, and this low-complexity single-parameter read tool is otherwise well covered by the prerequisite and forum caveat. Only pagination/no-archive behavior is left unspecified.

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% for the single parameter, so the description must compensate, and it does by telling the agent where server_id comes from (list_servers). It doesn't describe the ID's format, but the key semantic — provenance — is covered.

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 a server's channels and active threads) plus a scope detail (category order), so the agent knows exactly what comes back. It doesn't explicitly contrast itself with read_messages or read_server_recent, so the sibling differentiation is only implicit.

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?

Gives a clear prerequisite chain ('server_id: a server ID from list_servers') and a concrete routing rule for forum channels ('read their threads instead'), which points the agent elsewhere for that case. It stops short of stating the general boundary versus read_messages for non-forum channels.

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

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

With no annotations, the description carries the burden and does disclose a meaningful constraint: only servers the bot itself is a member of are returned, which prevents false expectations about completeness. It doesn't discuss ordering or pagination, but for a zero-parameter read with an output schema that gap is minor.

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 single front-loaded sentence with the key scoping qualifier at the end and zero filler. Nothing is wasted.

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?

Zero parameters plus an existing output schema mean return values need no explanation; the only residual gaps are ordering and whether all guilds are guaranteed to be returned. For a simple enumeration tool this is close to 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?

The tool takes no parameters, so there is nothing to disambiguate; baseline 4 applies. The description correctly implies no filtering options are available.

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 gives a specific verb (List) and resource (Discord servers/guilds), and even clarifies the synonym 'guilds' and the scope 'the bot is a member of'. It is clearly distinct from siblings like list_channels and read_messages, though it doesn't name them explicitly.

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?

Usage is only implied: an agent can infer this is the discovery step before list_channels, but the description never states when to use it versus alternatives or what to do next. No exclusions or prerequisites are mentioned.

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

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

With no annotations, the description carries the full burden, and it does add value beyond structured fields: chronological ordering, a hard cap of 500 that the schema does not mention, and the paging mechanism via 'before'. It still omits the safety profile (read-only nature), permissions/scope requirements, and what a returned message looks like, which matter for a tool with zero annotation coverage.

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 behavior sentence is front-loaded, followed by a compact aligned parameter glossary. Every line carries information; the minor cost is the slightly list-like layout, but nothing is wasted.

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?

For a four-parameter tool with no output schema and no annotations, the invocation side is well covered (params, ordering, paging, cap). The missing piece is the response side: without an output schema, the description should say what a message object contains or how many/how paging metadata is returned.

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%, so the description must compensate, and it largely does: all four parameters are explained, including where channel_id originates, limit's default and max, since_hours' time-window semantics with a concrete example, and before's use for backward paging. Only limit's default is redundant with 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 ('Read messages from one channel, thread, or DM') plus an ordering guarantee ('oldest first'), which tells an agent exactly what it gets back. It does not explicitly contrast with the sibling read_server_recent, so the agent must infer that this one is scoped to a single channel/thread rather than a whole server.

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?

Useful routing hints are present for parameters: channel_id must come 'from list_channels' and 'before' is for paging further back. However, there is no explicit statement of when to prefer this over read_server_recent, and no exclusions or prerequisites, so the when-to-use guidance is implied rather than stated.

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

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

With no annotations, the description carries the full burden and does disclose non-obvious runtime behavior: empty channels are skipped without an API call, and unviewable channels surface in a 'skipped' list with a reason. It omits ordering of returned messages, rate-limit behavior, and the overall shape of the collected output, keeping it short of a 5.

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 capability statement is front-loaded in one sentence, then parameters are given in a compact aligned block; nothing is padded. The aligned-parameter format is slightly unusual but every line carries meaning, so it stays close to optimal.

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?

For a 3-parameter aggregation tool with no output schema and no annotations, the description covers inputs well and hints at the 'skipped' output key, but never sketches what a collected message looks like or how results are ordered. Adequate, with a real gap on the return side.

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%, yet the description documents all three parameters: it names the source of server_id (list_servers), explains since_hours as lookback with its default, and gives per_channel_limit a default of 100 plus a max of 500 that appears nowhere in the schema. That fully compensates for the empty schema descriptions.

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 with scope: 'Collect recent messages from every channel and active thread in a server.' The server-wide aggregation is clear, but it never explicitly contrasts itself with read_messages (single-channel), so the agent must infer the split from the word 'every'.

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?

Usage is implied by 'recent' plus the since_hours default, and the pointer that server_id comes from list_servers is a useful grounding cue. There is no explicit when-not statement or named alternative, so the agent gets context but no routing rule.

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

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

With no annotations, the description carries the full burden and does well: it discloses that messages post as the bot, that content over 2000 characters is split at line breaks, and that @everyone/@here/role mentions never ping while user mentions do. It omits permission requirements, rate limits, and failure behavior, which keeps it short of a 5.

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?

Front-loaded with the core action, then a confirmation rule, then a compact parameter list — no filler sentences. The inline param block is slightly list-like but earns its space given zero schema coverage.

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?

For a three-parameter mutation tool with no annotations and no output schema, it covers action, preconditions, parameter meaning, and message edge cases. The remaining gap is the return value (e.g., the created message ID) and error behavior, which matter for a write operation with no output schema.

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% with no parameter descriptions, so the description must compensate, and it documents all three: channel_id (channel or thread ID), content (with the 2000-character splitting rule), and reply_to (message ID to reply to). The splitting rule in particular is behavior the schema cannot express.

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 first sentence gives a precise verb and resource ('Post a message as the bot') plus the destination scope (channel, thread, or DM). It is unambiguously distinct from the read-only siblings (read_messages, list_channels) without needing the schema.

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?

It specifies a mandatory precondition workflow: show the target channel and exact text and obtain confirmation before calling. It does not name alternatives, but among the listed siblings there is no competing send tool, so the omission is minor rather than misleading.

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