search_instances

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

No annotations are supplied, so the description carries the full burden. It does disclose pagination behavior, partial matching, and that detailed records are returned, but it omits read-only/safety profile, permission requirements, and the cap on result size that actually lives in the schema, so the disclosure is partial.

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 a clear purpose sentence, which is good, but the bullet list largely duplicates the input schema's field/parameter descriptions, and the closing line ("optimized for large-scale environments with intelligent filtering") is unverifiable marketing filler.

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?

The output schema covers return shape and the schema covers all parameters, so the description only needs to add routing and behavioral context. It provides pagination context but leaves the critical gap: no guidance on disambiguating from the numerous get_instance* siblings in a crowded namespace.

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%, so all five parameters are already documented in the schema. The description restates the same facts (partial matching, case sensitivity, searchable fields) without adding new syntax, ordering, or edge-case meaning, which makes baseline 3 correct.

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 ("Search for OpenStack instances") and enumerates the searchable fields, so the agent knows what the tool does. However, it never distinguishes itself from the many overlapping siblings (get_instance, get_instance_by_name, get_instance_details, get_instances_by_status), so an agent cannot tell from this text which one to pick.

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 by the word "search" plus the criteria list; there is no explicit guidance on when to use this over get_instance_by_name (exact lookup) or get_instances_by_status (filter by status). No prerequisites or exclusions are stated.

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