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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, clearly indicating safety. The description adds value by detailing the output (matched title, year, provider list grouped by category, a link) but does not explicitly reaffirm the idempotent or open-world nature. With annotations covering safety, the description provides moderate additional context.

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 concise at about 10 sentences, front-loads the purpose, and uses a list for markets and providers. It is well-structured and informative without excessive verbosity, though it could be slightly shorter.

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 only 2 parameters with full schema coverage, no output schema, and the presence of annotations, the description provides sufficient context: output structure, example providers, and a link for more details. It does not cover error cases (e.g., title not found), but overall it is complete enough for its complexity.

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?

Input schema coverage is 100%, so baseline is 3. The description adds meaningful extra information: title can be 'English, romanized, or original-language', with examples; for country, it lists the 30 codes and notes default to IN. This goes beyond the schema description, justifying a 4.

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 clearly states the tool's purpose: 'Find which streaming services carry a specific movie or TV show in a specific Asian or Middle Eastern country.' It specifies the scope (30 markets) and provides examples of streaming services. It implicitly distinguishes from siblings like 'search_titles' and 'whats_new_on' by focusing on availability queries.

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 says 'Use this tool whenever a user asks "where can I watch X in Y" for any of these 30 markets' and lists the markets. It also says 'Best for queries about availability on...' which gives context. However, it does not mention when not to use it or differentiate from sibling tools, so a 4 is appropriate.

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