Astroclaw

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is covered. The description adds useful semantics — that the result is derived deterministically via a stable name hash — but says nothing about auth needs, rate limits, or the failure case.

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 that carries the primary source (birthdate) before the fallback. It is well-sized with almost no waste, though the parenthetical slightly interrupts the flow.

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 two-optional-parameter lookup with no output schema, the description covers the roles of both inputs adequately. It does not state what happens when both parameters are omitted (required count is 0), leaving the zero-argument behavior undefined.

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 only 50% (agent_name is undocumented in the schema), so the description must compensate, and it does: it explains that birthdate may be a deployment or creation date and that agent_name is used as a stable-hash fallback. This adds meaning beyond the bare 'YYYY-MM-DD' schema hint.

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+resource: 'work out which zodiac sign an agent should use', making the resource and target clear. It is distinguishable from get_horoscope and list_signs by virtue of computing a sign rather than listing or fetching a horoscope, though it never names or contrasts those siblings directly.

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 gives real internal usage logic: prefer birthdate, and only fall back to a stable hash of agent_name 'failing that'. However, it offers no guidance on when to choose this tool over get_horoscope or list_signs, and no exclusions or preconditions.

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?

Annotations already cover readOnly, idempotent and closed-world. The description adds genuine behavior beyond them: the latest-day default and the sign-derivation fallback when sign is omitted, which is non-obvious logic an agent needs.

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?

Two sentences, front-loaded with the core action followed by defaults and fallback. No filler; every clause earns its place.

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 simple read-only lookup with no output schema and no required params, the description is sufficient: it covers the default date and the sign-derivation path. Only minor gap is that the return shape/format is unaddressed, though no output schema obligated it.

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 baseline is 3. The description adds relational semantics the schema lists only individually: birthdate or agent_name are used to derive sign, and the sign is the primary selector. That cross-parameter dependency is real added value.

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: 'Get the daily Astroclaw horoscope for a zodiac sign.' Clear what it does, though it never distinguishes itself from the siblings find_sign or list_signs, so an agent must infer the boundary.

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 clear operational context: defaults to the latest published day, and routes the agent to pass birthdate or agent_name when the sign is unknown. No explicit when-not-to-use or sibling comparison, but the fallback path is well communicated.

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?

Annotations already establish this as a safe, idempotent, non-open-world read. The description adds valuable behavioral context by specifying the returned data (signs, date ranges, latest forecast date), which is critical since no output schema exists; it does not repeat annotation details.

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 no wasted words. The verb and scope appear immediately, and the sentence earns its place by clarifying the returned content.

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 simple, parameterless list tool with rich annotations and no output schema, the description adequately conveys what will be returned. It does not explain ordering or pagination, but those are negligible for a fixed twelve-item list.

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 zero parameters, so the schema provides no parameter semantics. The baseline score of 4 applies for a parameterless tool; the description appropriately adds no parameter information.

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 provides a specific verb ('List') and resource ('the twelve zodiac signs') and enumerates what is returned (date ranges and latest forecast date). It implicitly distinguishes itself from find_sign and get_horoscope by scoping to the complete set of twelve signs, though it never names those siblings 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?

The description offers no when-to-use guidance, no prerequisites, and does not mention alternatives like find_sign or get_horoscope. It simply states what the tool returns, leaving the agent to infer appropriate usage.

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