Find a gene by official symbol in NCBI Gene to retrieve its full name, chromosome, cytogenetic location, aliases, and summary for biomedical literature review.
Look up a gene in NCBI Gene: full name, chromosome, cytogenetic location, aliases and summary.
| Name | Required | Description | Default |
|---|---|---|---|
| symbol | Yes | Official gene symbol, e.g. 'BRCA1' | |
| taxon_id | No | NCBI taxonomy ID; 9606 = human, 10090 = mouse |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety and repeatability profile is covered. The description adds the concrete return contents, which is useful since no output schema exists, but it says nothing about unknown-symbol behavior, default-species scope, or NCBI rate limits.
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 filler; the action is stated first and the return payload second. The trailing comma list of fields is dense but earns its place given there is no output schema.
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, two-parameter lookup whose annotations carry the safety profile and whose schema is fully documented, the description covers purpose and return shape adequately. It stops short of the operational caveats (species default, not-found handling) that would make it fully self-sufficient.
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%, with both 'symbol' (example 'BRCA1') and 'taxon_id' (9606 = human, 10090 = mouse) fully documented in the schema. The description contributes no additional parameter meaning, so the baseline of 3 applies.
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?
Specific verb ('look up') plus resource ('a gene in NCBI Gene'), and it enumerates the fields returned (full name, chromosome, cytogenetic location, aliases, summary), so the agent knows exactly what it gets. It does not, however, distinguish itself from the sibling lookup_protein, which follows the same lookup pattern and could plausibly be confused for the same request.
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: an agent can infer it should call this when it has a gene symbol and needs gene-level metadata. There is no explicit when-to-use, no when-not-to-use, and no pointer to search_pubmed, get_abstracts, or lookup_protein for adjacent needs.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.