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

No annotations are provided, so the description carries the full burden of behavioral disclosure. However, it does not explicitly state whether the operation is read-only, describe the response shape, or clarify pagination behavior. The cryptic 'How-to rides as description (alias of custom_instructions) — same name create_playbook / update_playbook write' is confusing and does not meaningfully disclose behavior. The only behavioral hint is 'Filter by category or status,' which is already evident from the schema.

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 short and front-loaded with the primary action. However, the sentence 'How-to rides as description (alias of custom_instructions) — same name create_playbook / update_playbook write' is obscure and likely to confuse rather than help. The final 'Routing: What Playbooks exist → use this' repeats the earlier 'Use when asking what playbooks exist,' making it somewhat redundant.

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?

Given the lack of an output schema and annotations, the description should compensate with clear behavioral and domain context. It partially does via usage guidance and scope, but the 'How-to rides' note is unexplained and likely to mislead an agent. The description also does not specify what the returned list contains or how results are ordered/paginated beyond the schema's 'limit' parameter.

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 100% (all four parameters are described in the schema), so the baseline is 3. The description only repeats 'Filter by category or status,' which adds no new meaning beyond the schema's parameter descriptions. It does not clarify the semantics of companyId beyond what the schema already says ('you must be a member').

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 opens with a specific verb and resource: 'List Playbooks for the company (growth_tactics — the Plays rail).' It also clarifies the intended use via 'Use when asking what playbooks exist' and 'Routing: What Playbooks exist → use this,' making the tool's purpose unambiguous and distinguishable from sibling list tools.

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 explicitly states when to use the tool: 'Use when asking what playbooks exist, or before run_playbook / update_playbook.' It also mentions related alternatives (run_playbook, update_playbook) and the routing statement reinforces the primary use case. It does not explicitly state when not to use it, but the guidance is clear and actionable.

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