mcp-server-ads

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

Annotations already declare readOnlyHint=true and destructiveHint=false, indicating a safe read operation. The description adds valuable behavioral context beyond annotations: it specifies a limit ('Provide up to 2000 bibcodes at once'), which is a rate limit or constraint not covered by annotations. It also implies the tool returns metadata (e.g., for 'retrieving metadata'), though this is partially covered by the output schema. No contradictions with annotations are present.

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 highly concise and well-structured: three sentences that are front-loaded with the core purpose, followed by usage context and a key constraint. Every sentence adds value—no wasted words or redundancy. It efficiently communicates essential information without unnecessary detail.

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 tool's complexity (5 parameters, one required), rich annotations (readOnlyHint, destructiveHint), and the presence of an output schema, the description is mostly complete. It covers the purpose, usage context, and a key constraint (2000 bibcode limit). However, it could be more complete by explicitly differentiating from sibling tools or detailing error cases, but the annotations and output schema reduce the burden on the description. The description adequately supplements the structured data for effective tool selection.

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%, meaning the input schema fully documents all parameters (bibcodes, query, fields, sort, rows). The description adds minimal parameter semantics beyond the schema: it mentions 'bibcodes' in the context but doesn't explain their format or source, and it implies the tool handles 'filtering, sorting, or retrieving metadata,' which aligns with the query, sort, and fields parameters. Given the high schema coverage, a baseline score of 3 is appropriate as the description doesn't significantly enhance parameter understanding.

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: 'Search within a specific set of bibcodes (big-query)' and 'Useful for filtering, sorting, or retrieving metadata for a known set of papers.' This specifies the verb (search), resource (bibcodes/papers), and scope (within a known set). However, it doesn't explicitly differentiate from sibling tools like 'ads_search' or 'ads_object_search' beyond mentioning 'big-query' and 'known set of papers.'

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 provides some implied usage context: 'Useful for filtering, sorting, or retrieving metadata for a known set of papers.' This suggests it's for when you already have bibcodes. However, it doesn't explicitly state when to use this tool versus alternatives like 'ads_search' (which might search the full database) or other siblings, nor does it mention any exclusions or prerequisites beyond the bibcodes requirement.

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